Olo Proudfoot was considered to be a skilled fighter when he fought during the Battle of Bywater. In order to prevent the land from be invaded by the Ruffians again, Olo became a loyal guard in the Shire.
On September 12, 3001, he and his son attended Bilbo's Farewell Birthday Party. When Bilbo disappeared using his Magic Ring, which turns out to be the One Ring, Olo was surprised by this and left the party with his son. However, when he learned that Bilbo had left the Shire, he was very crossed by this.
Sometime when the Sauron was planning to lead his dark forces throughout the corners of Middle-earth, Olo was among those that joined the Shire Company under he leadership of Will Whitfoot. He participated near the end of the Battle of Pelennor Fields where he slew several Orcs that were retreating by the combined forces of the west and east. He helped gather the wounded and was very happy to see Merry and Pippin.