frontier in relative secrecy, and crossed the frontier at Thuin near Charleroi on 15 June 1815. The French drove in Coalition outposts and secured Napoleon's favoured "central position" – at the junction between Wellington's army to his north-west, and Blücher's Prussians to his north-east. Wellington had expected Napoleon to try to envelop the Coalition armies by moving through Mons and to the west of Brussels. Wellington feared that such a move would cut his communications with the ports he relied on for supply. Napoleon encouraged this view with misinformation. Wellington did not hear of the capture of Charleroi until 15:00, because a message from Wellington's intelligence chief, Colquhoun Grant, was delayed by General Dörnberg. Confirmation swiftly followed in another message from the Prince of Orange. Wellington ordered his army to concentrate around the divisional headquarters, but was still unsure whether the attack in Charleroi was a feint and the main assault would come through Mons. Wellington only determined Napoleon's intentions with certainty in the evening, and his orders for his army to muster near Nivelles and Quatre Bras were sent out just before midnight. The Prussian General Staff seem to have divined the French army's intent rather more accurately. The Prussians were not taken unawares. General Zieten noted the number of campfires as early as 13 June and Blücher began to concentrate his forces. Napoleon considered the Prussians the greater threat and so moved against them first with the right wing of the Army of the North and the Reserves. Graf von Zieten's I Corps rearguard action on 15 June held up Napoleon's advance, giving Blücher the opportunity to concentrate his forces in the Sombreffe position, which had been selected earlier for its good defensive attributes. Napoleon placed Marshal Ney in command of the French left wing and ordered him to secure the crossroads of Quatre Bras towards which Wellington was hastily gathering his dispersed army. Ney's scouts reached Quatre Bras that evening. 16 June Quatre Bras Ney, advancing on 16 June, found Quatre Bras lightly held by Dutch troops of Wellington's army. Despite outnumbering the Anglo-allies heavily throughout the day, Ney fought a cautious and desultory battle which failed to capture the crossroads. By the middle of the afternoon Wellington had taken personal command of the Anglo-allied forces at Quatre Bras. The position was reinforced steadily throughout the day as Anglo-allied troops converged on the crossroads. The battle ended