Preparations to defend the line of the San were connected to the unfavourable developments in the situation on the front and the desire to recreate a continuous and stable line of defence. On September 6, the Commander-in-Chief, Marshal Edward Rydz-Śmigły decided to withdraw all units on the left bank of this river past the Vistula. The idea was to create a continuous front line based on the line of the rivers Narew–Biebrza–central Vistula. The southern section of the defence was to be based on the Dunajec River and then on the San River. The defence of the Dunajec and Vistula lines to Annopol was to be carried out by the combined forces of the “Carpathians” and “Cracow” Armies under the general command of Major General Kazimierz Fabrycy. Were it not possible to maintain this line, the troops were to retreat east and depend on the San.
On the morning of 7 September, General Fabrycy issued the first operational order outlining the general intentions of the Małopolska army’s command. The army was divided into two groups: “Cracow” Army (commander Major General Antoni Szylling) and the “Southern” Operational Group (commander Major General Kazimierz Łukoski). The latter included two infantry divisions (11th and 24th) and two mountain brigades (2nd and 3rd). The order generally outlined the rules of the retreat east. The final effect of this retreat was to be the defence of the Vistula–San line. The army commander’s reserve was to be concentrated in the region of Przemyśl and it was to include the 10th Motorised Cavalry Brigade transferred from the numbers of the “Cracow” Army. The sappers’ commander in the “Lesser Poland” army was to organise the redeployment of all the corps formations [Polish: jednostki pozadywizyjne] of sappers beyond the San River, where the civilian labour forces provided by the commander of the bases would immediately start building obstacles and fortifications.
General Fabrycy also issued orders regarding the temporary manning of the defensive line on the San River. Given the rapidly changing situation on the front, the intention to create rear-echelon parts of large formations failed, especially those who were to be concentrated in the western and central parts of Poland. The subunits mobilised at the beginning of September 1939 in the San garrisons, directly from the barracks or from railway transports, were sent to fill the defence lines on the San or to the advanced positions of individual bridgeheads. For example, the 22nd light artillery regiment stationed in Przemyśl formed two artillery divisions: for the 36th Reserve Infantry Division and the “Prussia” Army. The first of the divisions (II/40) was unloaded from transport at the railway station in Leżajsk on 8 September and sent to the defence of Jarosław; the second (50) remained in Przemyśl to support the city’s defence. Meanwhile, in Jarosław, based on the 39th Lviv Infantry Regiment [Pułk Piechoty Strzelców Lwowskich], the 3rd Battalion of the 154th Infantry Regiment (commander Lieutenant Colonel Franciszek Herzog) was mobilised, which, on account of new orders, was sent to Nowosielec near Przeworsk to defend the Cracow–Lviv road (now national road No. 94). Lieutenant Colonel Herzoga’s battalion held its positions until the evening of 9 September, when it was ordered to leave its posts and man the bridgehead in Kuryłówka. It is worth noting that the rear echelons, in terms of equipment, were full-fledged combat formations. However, due to being organised through general mobilisation, their weakness was that they needed harmonisation and coordination of individual subunits. The supplies of the march battalion formed in the San garrisons were much worse, insufficiently equipped with artillery and machine guns. Also in this case, the synchronisation of troops left much to be desired.
The importance of the organized defence on the San increased and became urgent after 7 September, when, as a result of mistakes made by General Fabrycy, in the region of Tuchów, the 24th Infantry Division of Jarosław was partially dispersed by the strong armoured vehicles of the German 4th Leichte-Division. The commander of the 24th Infantry Division, certified officer Bolesław Krzyżanowski arbitrarily decided to change the retreat axis, moving it further south to the Frysztak–Wysoka–Strzyżów line. German high-speed units from the XXII Motorised Corps followed by units of the XVII Army Corps (44th and 45th infantry divisions) began to pour into the gap between the “Cracow” Army and the troops of the “Southern” Operational Group. The 10th Motorised Cavalry Brigade of certified officer Stanisław Maczek attempted to stop the advance of the German high-speed formations. However, the Polish formation was too weak and outnumbered to put up tough resistance against the enemy, and all they could do was slow them down. That same day, the German 1st Mountain Division near Krępna and Gładyszów broke the defence at the junction of the 2nd and 3rd Mountain brigades and penetrated the Polish grouping.
On 9 September, Fabrycy from the “Lesser Poland” Army’s berth in Siedliska near Przemyśl issued new orders to defend the San line: from the estuary of the river to Jarosław, the defence was to be led by Brigadier General Mieczysław Boruta-Spiechowicz (commander of the “Boruta” Operational Group in “Cracow” Army); the defence of the river in the section from Jarosław to Przemyśl was to be commanded by Brigadier General Wacław Wieczorkiewicz, while the direct command of the defence of Przemyśl was taken by Brigadier General Jan Chmurowicz; the defence of the San line in the Sanok region (from Mrzygłód to Lesko) was organised by the commander of the 3rd Mountain Brigade, Colonel Jan Stefan Kotowicz.
On the afternoon of 9 September, an order came to the staff of the “Lesser Poland” Army which briefly specified its main task: Maintain the general Jarosław–Przemyśl line and then south to the Hungarian border. Do not allow the enemy to penetrate beyond the San River line from Jarosław to Sandomierz. The success of all planned actions of the Commander-in-Chief rests with the completion of this task. The Chief Command’s order also said that the 35th Infantry Division had been sent to meet the needs of the army as well as Brigadier General Józef Olszyna-Wilczyński’s group (10 infantry battalions and 5 artillery batteries) and two motorised divisions with the heaviest artillery. However, it would take these forces several days to reach their defensive positions. An innovation in the order for General Fabrycy was that the defence line south of Przemyśl did not have to rely on the San River. At the time when the headquarters of the “Lesser Poland” Army stationed in the fort of Siedliska near Przemyśl received this order, the leading German XXII Motorised Corps were arriving in Rokietnica, only 20 kilometres from the San River. Moreover, on the evening of 9 September, the Germans captured Sanok and the patrols of mountain shooters crossed the San as in the summer of 1939 the river was not a serious terrain obstacle.
In times of drought, the San was shallow.
From its springs near the Użocka Pass to Sanok, the San is a mountain river that crosses the mountain ranges. Downstream of the Osława estuary, the river changes in character, mainly in terms of the water flow speed and the riverbed composition, which contains sand and gravel. The character of the river valley also changes: the relative heights of the hills and the bank of the slope decrease. From Sanok to Przemyśl, the San is a mountain-lowland river. From the estuary of the Wiar near Przemyśl to the estuary of the Vistula River, the San is a lowland river. In this section, the river is 70–200 m wide, its banks are sometimes steep and precipitous, up to 6 metres high, the depth ranges from 1.5 to 5 m; the bottom of the river is gravel and rock.
In 1939, there were a total of sixteen bridges on the river section between Lesko and the estuary to the Vistula, including four railway bridges; in addition, there were several dozen ferry crossings and numerous fords on the river. The water level had a significant impact on the value of the river as a defence line. Based on many years of observations and measurements, conducted from 1870, it was found that the lowest water levels of the San are in September and October. The summer of 1939 was extremely hot and dry. If we can believe the press reports, in August 1939 there were only three rainy days in the San basin (3, 8, and 9 August) and one day with light showers (26 August). The atmospheric high which persisted for many weeks had an impact on the state of the San waters. In 1939, one of the lowest water levels in history was recorded for this river – the minimum indications of the water gauges were not broken until 1961. The destruction of the bridges – Polish sappers blew up or burned practically all of them – could delay the enemy’s actions by only a few or several hours. One could practically walk across the San with one’s trouser legs rolled up. This is confirmed by numerous photos taken by German soldiers.
“The front on the San is fiction”
The defence lines on the San near Jarosław were manned from the morning of 9 September. Its organisation on the right bank of the river, in the section from Radymno to Sieniawa, was led by Lieutenant Colonel Jan Wójcik. This position was meant to be taken over by three divisions. By the time they arrived, the region of Jarosław was to be defended by only three infantry battalions supported by several guns. The lack of communication hampered the organisation of the defence. It wasn’t until the evening that the bridge in Kuryłówka was manned by one of the battalions of the 12th Infantry Division. On the evening of 9 September, the defence line on the critical section of the river between Radymno and Kuryłówka, where an attack by two German high-speed divisions was expected, was meagre. In total, there were just over four infantry battalions supported by four artillery batteries. These forces were sufficient to guard the San line but not to effectively defend it.
The success of the entire operation depended on manning the line with large formations. The main weakness of the plan developed by Fabrycy and his staff was the assumption that the defence positions would be taken by large formations already engaged in the fight against Germany, immediately after leaving the foreground, without being able to rest, regroup, resupply personnel and equipment, etc. Under “textbook” conditions, huge formations that were thus far engaged in combat should have been sent through the defence lines to carry out the necessary reorganisation at the rear of the front, simultaneously serving as a reserve. One may wonder to what extent the situation in the Radymno–Sieniawa section, where the main pressure of the German rapid troops appeared, would be improved by the presence of the 38th Reserve Infantry Division. Still, on the morning of 8 September, General Fabrycy considered sending it to the region of Medyka. However, this division stood for the entire next day in the area of Dobromil, so about one and a half days’ walk from Medyka, and two days from Radymno. The command of the 38th Reserve Infantry Division only received an order to move “about 10 km north of Przemyśl” on 9 September at 10 p.m.
On 9 September, in the evening, the units of the 10th Cavalry Brigades withdrew from Łańcut and headed either directly to Jarosław or Sieniawa. In the morning on 10 September, Colonel Maczek arrived in Jarosław. There he met with General Wieczorkiewicz, who acquainted him with the situation in the defence sector. Maczek did not hide his disappointment with the size of the forces that were meant to defend Jarosław. More than twenty years after the war, he described this experience as follows: “It will be a painful surprise for me and all my soldiers when, after the nightmare of gathering brigade units and heading to Jarosław, which was still free, I will find almost complete desolation on the Polish line of ‘Maginot’ or ‘Siegfried’. One infantry battalion in Jarosław itself, some two or three batteries across the San River, news that some loose platoons are wandering about here and there, rarely companies, not even knowing what their task is. The front on the San is fiction – it is no less a Fata Morgana than the vision of an oasis above a spring with lush vegetation for the weary eyes of a wanderer in the desert. I still cannot believe it! After all, not only did we imagine the main Polish defence on the San, which we eagerly desired and believed in, but even the guidelines of the “Carpathians” Army’s command clearly defined our role in delaying, to give those few precious days to solidify the defence on the San!”
The general situation on the southern section of the front is equally accurately reflected in the memoirs of General Kazimierz Sosnkowski: On 10 September, the front of the “Carpathians” Army only existed figuratively, comprising individual focuses of resistance, scattered scarcely over a large area without communication between each other. These were mostly remnants of divisions that had already been broken several times, assembled temporarily into new formations but devoid of internal organisational cohesion. The road to Lviv along the Subcarpathian routes was wide open to the opponent’s forces, who had crossed the Slovak border in recent days with a wide front. North of the Przemyśl road, almost all directions to Lviv were open to the Germans, except for the routes from Jarosław and Radymno, for the time being, blocked by the 10th Cavalry Brigade.
The general situation was not improved by the fact that the leading units of the “Boruta” Operational Group reached the villages located in the lower course of the San River. On 10 September, the 6th and the 21st mountain divisions began crossing the eastern side of the river via the bridges in Brandwica (Rozwadów), Zarzecze (Nisko), Ulanów, Krzeszów, and Kuryłówka.
Breaking the defence
Fighting in the outskirts of Jarosław continued throughout the day on 10 September. When the tank attack was repelled in the afternoon, the Germans limited themselves to reconnaissance and airstrikes. The situation in the area of Radymno and Tryńcza was much worse. Column 4 of the Leichte-Division, which reached Rokietnica in the late hours of 9 September, attacked Radymno at around 5 a.m. the next day and drove the Polish company out of the city after a short fight. Although the Polish troops managed to blow up the road bridge over the San River, the Germans captured a small bridgehead on the right bank of the river. While between Tryńcza and Dębno, a German armoured motor vehicle crushed the battalion of Lieutenant Colonel Herzog. In the night of 10/11 September, following General Fabrycy’s order, the 10th Cavalry Brigade moved east, while the remaining units defending Jarosław positioned themselves on the eastern bank of the San, in the Garbarze-Szówsko region. The bridge over the San River in Jarosław was blown up.
The departure of the 10th Cavalry Brigade towards Jaworów significantly weakened the Polish defence in the Jarosław region. Already at dawn on 11 September, the 2nd Panzer Division opened strong artillery fire to start the attack on Polish positions even before noon. After a few hours, the Polish defence was ceased. The units of Lieutenant Colonel Wójcik’s grouping were largely destroyed, some only withdrew towards the Sieniawskie Forests.
On 11 September, the Germans limited themselves to breaking up the lean forces that manned the defensive frontiers on the San and building crossings through the San near Radymno and Jarosław. The next day, the German panzer teams began their raid to the north-east, in the general direction of Tomaszów Lubelski and Rawa Ruska. During the afternoon of 12 September, the units of the German 2nd Panzer Division occupied the Lubaczów–Oleszyce–Cieszanów communication junction, which seriously complicated the situation of the “Cracow” Army and had an impact on the defeat of the Polish forces in the battle at Tomaszów Lubelski.
On 13 September, also due to the advances of the German XXII Motorised Corps, Marshal Rydz-Śmigły decided to withdraw troops to the so-called Romanian Bridgehead, where they intended to endure until the start of the offensive in the west.
The fate of the defence on the San was settled after crossing the river on 11 September near Jarosław. The fighting on this river continued for a few more days but it was no longer of strategic importance.
The quotes used in the article are taken from the following publications:
Tadeusz Jurga, Obrona Polski 1939 [Defence of Poland 1939], Instytut Wydawniczy “Pax”, Warsaw 1990, p. 437 and 449.
Kazimierz Sosnkowski, Cieniom Września, przedmowa Andrzej Rzepniewski [To the Shadows of September, foreword by Andrzej Rzepniewski], Wydawnictwo MON, Warsaw 1988, p. 78.
Stanisław Maczek, Od podwody do czołga, Lublin–Londyn 1990 [From requisition to tank, Lublin–London 1990], Towarzystwo Naukowe KUL, Orbis Books (London) Ltd., p. 81.