Iain Henderson has taken over from fellow Ireland forward Rory Best as skipper of Pro14 side Ulster.
The versatile 27-year-old, who is currently in Ireland's World Cup training squad, has represented his home province on 105 occasions.
"I'm incredibly proud and excited to be appointed as club captain," he said.
"I had a good chat with [Ulster coach] Dan McFarland and I think we're closely aligned in terms of how we see Ulster moving forward."
Henderson has won 44 international caps and played in four of Ireland's games during the Six Nations Grand Slam success of 2018, while he also featured in 2014 and 2015 Championship wins.
His excellent form at club and international level was rewarded with a call up to the British & Irish Lions tour of New Zealand in 2017.
"When I've captained Ulster on previous occasions, it's been made a lot easier because of the presence of a number of great leaders around me," added Henderson.
"Our squad has a very low age profile and one of the most exciting things for me is seeing the hunger within the group and the players' desire to improve."
McFarland said Henderson "has demonstrated his ability to command respect through his professionalism and talismanic play".
He added: "Iain has a deep love for his province. He understands exactly what it means to wear the Ulster jersey and this rubs off on those around him."