The failure of Grant's 22 May assaults marked the beginning of the siege of Vicksburg, which is perhaps the most noted siege of the war. For over six weeks bad food, bad water and the searing sun of the Mississippi summer tormented the soldiers of both sides as well as the innocent citizens trapped inside Vicksburg. The siege was also a race against time as Pemberton tried to make his food and ammunition supplies hold out until relief could reach him while Grant strove to capture the fortress before Johnston's growing army at Jackson became too strong.
On 23 May, the day after the disastrous assaults, Grant began a two-day naval and land bombardment to keep the Confederate troops pinned down. He then began adjusting his lines. It was especially important to shift his troops to the left, for there was a two and one-half mile unoccupied stretch between McClernand's left and the river. This gap was not satisfactorily covered until Lauman's division of XVI Corps arrived from Tennessee on 28 May.
One important detail remained unfinished from the 23 May assaults. Grant for two days declined Pemberton's offer to declare a truce in order to bury the dead and collect the Union wounded still lying on the field. Finally he consented to a two-hour cessation of hostilities to begin at 1800 on 25 May. Soldiers of both sides took this opportunity to fraternize, trade, play cards, and survey each other's trenches as they went about their gruesome work. Sergeant William Tunnard of the 3rd Louisiana, who left a very vivid account of the siege, described