Toul controlled a railway line leading to Germany and it was vital for the Germans to secure it to resupply and reinforce their armies in northern France.

[3] The 125-meter-high Mont St.Michel to the north, the Dommartin-lès-Toul heights to the east, the Choloy plateau to the south-west and the absence of bomb-proof cover rendered the fortification vulnerable to artillery bombardment and the hills and villages nearby made it easy for hostile infantry to advance to its ramparts.

[4] On 14 August, Captain von Trotha's squadron from the 2nd Dragoons of the Guard attacked some chasseurs à cheval near Toul.

[5] Another demand for surrender came on 15 August, this time from Captain von Rosen of the 2nd squadron, 3rd Lancers of the Guard, whose men had advanced on the fortress under fire, though they suffered no losses.

[6] General of the Infantry Gustav von Alvensleben, commander of IV Corps, encouraged by Toul's weak resistance to these advance groups, decided on the early morning of 16 August to reconnoiter the fort and seize it by means of a coup de main.

[2] IV Corps' advance guard, consisting of the reinforced 14th Infantry Brigade, which included the 27th and 93rd Infantry Regiments, the 7th Dragoons, the 1st heavy and 2nd light batteries, two pioneer companies and the light bridge train and which was commanded by General von Zychlinski, received Alvensleben's order and deployed at Francheville at 1100, where the 2nd heavy battery had also been concentrated.

[9] At 1300, the 93rd Regiment's fusilier battalion advanced in skirmishing order against the northern face and reached the main ditch, opening fire on the garrison deployed at the north gate ravelin.

[12] At 1400, a German heavy gun fired eight rounds from a range of 80 meters at the gate near the St. Mansuy suburb to destroy it and bring down the drawbridge.

[4][17] By early September, the German besiegers had Etappen troops from III Prussian Army, the 4th and 6th fortress artillery companies and captured French guns from Marsal with which to bombard Toul.

[4] The French artillery continued firing on 11 September and the newly-arrived German commander, Frederick Francis II, Grand Duke of Mecklenburg-Schwerin, discontinued his own bombardment.

[18] The 34th Brigade was deployed on the Choloy plateau, the 33rd on both banks of the Marne–Rhine Canal and the Germans set to work closing in on the glacis from the north.

[18] The 5th and 6th heavy batteries of the 17th Infantry Division were deployed into pre-prepared positions on Mont St. Michel on 16 September to subdue the French fortress artillery, which had maintained its own fire.

[18] Carriages transported the guns to the artillery parks on the Choloy plateau and on the Côte Marine, while their emplacements were being constructed by infantry from Ecrouves.

[18] Colonel Bartsch, commander of the siege artillery, and Major Schumann, the senior engineer officer, planned the direction of the attack.

[21] German pioneers erected a bridge over the river at Pierre la Treiche on 20 September, while a detachment of Bavarian engineers destroyed a canal lock near the suburb of St.

[21] A German attempt to drain the ditch of the fortress by diverting the Vauban canal's water to the Moselle succeeded only partially.

[23] To cover the preparations, a rifle company occupied St. Evre on the night of 21–22 September and heavy guns and three field batteries bombarded the town throughout the day from Mont St.

[23] At 0530 on 23 September, 11 siege batteries with 62 guns and howitzers opened fire, while Frederick Francis watched the proceeding from the Côte Barine.

[23] The garrison was taken prisoner of war and sent to a bivouac on the Choloy road and the German 3rd Battalion, 90th Regiment and two rifle companies occupied the town in the evening.