The Hilton hotels brand has been reunited under single worldwide ownership in a £3.3bn ($5.7bn) deal.
The Hilton name has been two separate businesses since 1964
UK-based Hilton Group has sold its 400 hotels to separate American business Hilton Hotels Corporation (HHC).
The move reunites the Hilton hotel businesses for the first time in 41 years, following their split in 1964.
At that time, HHC sold off all its hotels outside the US. HHC is now adding some 240 global Hilton Group hotels to its existing 2,300 in the US.
Hilton Group, which is based in Watford, also owns the Ladbrokes gambling business and will be renamed Ladbrokes on completion of the deal.
Hilton Group said Sir Ian Robinson would continue as chairman of Ladbrokes while Christopher Bell would become chief executive.
Current Hilton Group chief executive David Michels is to transfer to the enlarged HHC.
"We believe this transaction delivers significant shareholder value," said Sir Ian.
"The board is fully committed to Ladbrokes, which it believes is a strong and valuable business which will be well placed to deliver growth and good returns."
Hilton Group added that following the sale it expected "a substantial amount of cash will be returned to shareholders" in the second quarter of 2006.
"I am very proud of the Hilton brand, which has consistently been acknowledged as one of the world's leading brands," said Mr Michels.
Hilton Group is to change its name to Ladbrokes
"I fully expect the enlarged company to grow and our customers can look forward to enjoying even more opportunities as a result of the strengths of the unified business."
The two firms first revealed in October that they were in talks over the sale.
Analyst Robert Lafleur of Susquehanna Financial warmly welcomed the deal.
"It makes sense for the companies to be consolidated so they're a unified, global lodging platform and it puts them on a par with their key competitors, who are Marriott and Starwood, both of which have integrated international platforms, so strategically the deal makes perfect and total sense," he said.