Gov. Ron DeSantis of Florida would normally be traversing the state this time of year, trumpeting his legislative accomplishments and the fellow Republican lawmakers who had fallen in line to achieve them. So it was during his first six years in office, especially as he prepared to run for president.

This year has been different, mostly because of one man. Daniel Perez, the Republican speaker of the State House of Representatives, clashed with Mr. DeSantis over how to crack down on illegal immigration; allowed a House investigation into a charity tied to the governor’s wife, Casey DeSantis, and insisted on passing a slimmer state budget than what the governor proposed, even if it meant dragging out the unusually bitter legislative session for an extra six weeks.

Mr. Perez, a 37-year-old Cuban American lawyer from Miami, may not have set out to become the governor’s adversary when he assumed his leadership role last year. His goal was to reassert his chamber’s power, “to be a coequal branch of government,” he said in an interview on Monday, the session’s final day.

Yet that was enough to shift the power dynamics in the Republican-controlled State Capitol, where lawmakers had spent years bending to the will of a popular governor who steadily expanded executive power.

Mr. DeSantis, who is term-limited and has one more regular session left, faced more resistance than ever before. The relationship between Mr. DeSantis and Mr. Perez got so rancorous that, at one point, Mr. DeSantis referred to House lawmakers as “treacherous.” Mr. Perez countered that the “emotional” governor was throwing “temper tantrums.”

In some ways, the conflict was the point, Mr. Perez said on Monday.

“We were able to have a difference of opinion,” he told reporters in Tallahassee. “We were able to reach a conclusion that maybe either the Senate or the governor didn’t agree with. That was our goal.”