Sir Terry Wogan acted as a bridge between Ireland and Britain, Irish premier Enda Kenny has said.
Leading tributes from his home country, the Taoiseach said the Limerick-born broadcaster gave endless entertainment to Irish as well as British viewers and listeners.
"It is with great sadness that I learned this morning of the passing of legendary broadcaster Terry Wogan," he said.
"Terry's humour and wit were unparalleled and he graced the top of his broadcasting profession for decades as a reassuring voice on the BBC.
"As an Irishman, Terry Wogan occupied a special place in British listeners' hearts and he acted in no small way as a bridge between Ireland and Britain.
"His always entertaining, and often unforgiving, commentary of the Eurovision Song Contest provided viewers here and in Britain with endless entertainment.
"Our deepest condolences go to his family at this time."
Irish president Michael D Higgin said he had learned with sadness of the death of "one of the great figures of broadcasting".
"His was a distinguished contribution to television and in particular to the medium of radio," he said of Sir Terry.
"People in Ireland will remember his early career in Irish broadcasting. On his move to Britain his voice became one of the most often quoted, favourite radio voices.
"Always proud of his origins in Limerick, he made many returns to his native country for television and radio projects.
"His rise to the top of radio listenership in the United Kingdom was a great tribute to his breadth of knowledge and in particular his unique, very personal sense of humour."
Ireland's Tanaiste Joan Burton credited the late broadcaster with being an inspiration to generations of Irish emigrants.
"While he spent most of his life in Britain, he was always proud of his Irish roots," she said.
"He provided inspiration to generations of emigrants who, like himself, had moved from Ireland to make better lives for themselves at a time when it wasn't always easy to be Irish in the UK."
Ms Burton added: "Terry Wogan made us all feel proud. He was more than just a broadcaster; he showed Ireland and the UK had more in common than divided us.
"My sympathies go to his wife Helen and their family."