This morning, Wogan's family released a statement saying he died after a short but brave battle with cancer.
BBC director general Tony Hall said: "Terry truly was a national treasure."
Earlier today, Eurovision.tv spoke with Guy Freeman, Head of Delegation for the BBC at the Eurovision Song Contest and Executive Producer of the 1998 contest in Birmingham.
"My fondest memory of Sir Terry was sitting next to him in the commentary box in Dublin in 1997. Not only was he having a great and hospitable time in his home country, but was also enjoying the rare treat of a scoring sequence that culminated in a UK victory. As soon as we came off air, with genuine modesty, he turned to me and asked me to please bear him in mind next year, if we were looking for a host. As if we would ever have asked anyone else!"
Looking back at the 1998 contest, the last one hosted on UK soil, Freeman said: "The roar of the crowd as he stepped on to the Eurovision stage in Birmingham was testimony to his huge popularity. All our thoughts are with his wonderful wife Helen and the family he loved."
Katrina Leskanich, who won the contest that year with her band Katrina & The Waves, shared her thoughts on Twitter, just like 1992 Eurovision Song Contest winner Linda Martin.
Singer Ronan Keating, member of Boyzone, co-host of the 1997 Eurovision Song Contest and author of the Danish entry for the 2009 contest, also reacted.
Devastated to hear of the passing of Sir Terry Wogan. A true gentleman a king of the airwaves. Our thoughts are with his family. #ThanxTerry— Ronan Keating (@ronanofficial) January 31, 2016
Presenter Graham Norton was given the impossible task of succeeding the hugely popular Eurovision commentator in 2009, after Wogan left the commentary booth for the last time after the Grand Final in Belgrade, in 2008.
He made it seem effortless and for a young boy in Ireland he made it seem possible. RIP Sir Terry Wogan. I'll raise a glass during song 9.— graham norton (@grahnort) January 31, 2016
Molly Smitten-Downes, who represented the United Kingdom at the 2014 contest with Children of the Universe, undoubtedly grew up with Wogan's commentary.
Awwww Terry Wogan ! 😥— M O L L Y (@mollysd) January 31, 2016
Wogan was born in Limerick, Ireland, and moved to Dublin at the age of 15. After a brief career in banking, the young Terry Wogan joined Irish broadcaster RTÉ as radio presenter. He joined the BBC in London at the age of 28.
This year's Irish Eurovision Song Contest participant and former Westlife singer Nicky Byrne also responded to Wogan's death.
Shocked with the news of @terry_wogan death. Met him many times in Westlife on his TV & Radio shows.— Nicky Byrne (@NickyByrne) January 31, 2016
Always a Gentleman,Always a smile
Within the Eurovision Song Contest community, fans reacted with disbelief following the passing of the much-debated former commentator. "It was hard not to have an opinion about Wogan's commentary. Fans either loved it, or they couldn't stand it," Sietse Bakker, Event Supervisor of the Eurovision Song Contest said to Eurovision.tv. "To many viewers in the UK and beyond, his name is forever connected to the contest. That is a remarkable achievement in itself," he concluded.
OGAE International, the largest Eurovision Song Contest fan club, referred to Wogan als "legendary".
Forbes journalist and Eurovision Song Contest pundit Ewan Spence of ESC Insight. Spence: "I've never had a Eurovision Song Contest without Terry’s presence (...) Every year when I watched the contest, he was there, as a personal guide through the music."
To former Norwegian Eurovision Song Contest commentator Jostein Pedersen, Wogan was his inspiration. Pedersen commented for broadcaster NRK in 1994 and from 1996 to 2005.
Cornald Maas started his career as Eurovision commentator alongside the Dutch 'Mister Eurovision' Willem van Beusekom, who passed away in 2006. On Twitter, Maas referred to Wogan as "eloquent master of irony".
Terry Wogan, eloquent master of irony, maar ook met groeiende hekel aan landen die 'zijn' UK negeerden, overleden #songfestival— Cornald Maas (@cornaldm) January 31, 2016
What are your best memories of Sir Terry Wogan?