The Battle of Liège began shortly after the morning of 5 August 1914, when German bombardment began on the eastern Belgian forts. That marks it chronologically as the first battle to take place during World War I, beginning shortly before the Battle of Mulhouse. The Imperial German troops were obliged to entrench and bring up heavy siege artillery. He laid siege to Liège, which he entered on 7 August 1914, but the last forts did not surrender until 16 August 1914.