St-Pierre, who would later win the middleweight title, held the belt for over 2,000 days before relinquishing it.
At the moment, Kamaru Usman is the reigning champion, having won the belt late in 2019.
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At UFC 235 on March 2, 2019, Kamaru Usman won his first UFC title with a victory over Tyron Woodley.
Usman, a former Ultimate Fighter alum, earned a successful title defense when he finished Colby Covington at UFC 245 on December 14, 2019. His current run stands at over 400 days.
For a brief period of time, Colby Covington was the interim UFC welterweight champion.
The outspoken fighter won the title by besting Rafael dos Anjos at UFC 225 in Chicago on June 9, 2018. On September 8, he was stripped of the belt.
For nearly 1,000 days, Tyron Woodley held his head high as the welterweight champion of the UFC.
Woodley claimed the title with a knockout of Robbie Lawler at UFC 201 in Atlanta on July 30, 2016. Along the way, he topped Stephen Thompson, Demian Maia and Darren Till.
MMA veteran Robbie Lawler finally reached the pinnacle of the sport when he topped Johny Hendrick at UFC 181 on December 6, 2014.
For 602 days, Lawler was the champion, scoring victories over Rory MacDonald and Carlos Condit. He would drop the title to Tyron Woodley.
The man that pushed Georges St-Pierre to his limits, Johny Hendricks won the UFC welterweight title in a match with Robbie Lawler at UFC 171 on 2014.
The two would have a rematch at the end of the year, with Lawler winning the title.
For a brief period of time, Carlos Condit held the interim UFC welterweight title.
He captured that title at UFC 143 in 2012 with a victory over Nick Diaz.
As previously mentioned for the first three years of the decade, Georges St-Pierre was the welterweight division.
St-Pierre, in his second reign, held the title for over 2,000 days, earning defenses in this decade over Dan Hardy, Josh Koscheck, Jake Shields, Carlos Condit, Nick Diaz and Johny Hendricks.