The British had been uncertain about the value of taking Baghdad due to its limited strategic value but eventually saw it as a symbolic goal; in addition it was seen as a way to close a pincer on the Turks with British advances from Baghdad and Russia pushing south from Mosul. That was not to be: at this same moment the February (March New Style) Revolution was under way in Petrograd.
Maude marched his main force up the east bank of the Tigris, arriving March 8 at the banks of its big tributary the Diyala. With the Turks defending the opposite banks of the Diyala, Maude moved most of his force downstream and crossed to the west bank of the Tigris. Detecting the movement (both sides had aircraft now with Germans flying for the Turks), Khalil moved most of his force to the west bank, leaving one regiment on the Diyala. The British soon pushed this aside, and Khalil, facing British advances on both banks, resolved on a retreat from Baghdad. By the evening of March 10, the Ottoman evacuation of Baghdad was under way, with no major battle having been fought.
On the next day, March 11, the British and Indian forces entered Baghdad. The northward advance would be put on hold after Baghdad as the war unfolded on other fronts. Photo of Maude entering Baghdad on March 11, 1917: