The Lions began life with humble beginnings in 1888, with sporting entrepreneurs Alfred Shaw and Arthur Shrewsbury putting together a 22-man squad from England, Scotland and Wales for a marathon 54-match tour New Zealand and Australia.
The tour was not without controversy and tragedy, though. Jack Clowes was banned from playing for accepting expenses for clothing, while tour captain Robert Seddon drowned while sculling on the Hunter River. A number of the matches played during the Australia leg were played under Australian or Victorian Rules as they guaranteed bigger crowds - and larger profits for the organisers.
While the inaugural tour was unsanctioned, three years later the squad had the backing of the RFU - while the costs of the trip to South Africa were underwritten by the Cape Colony prime minister, Cecil Rhodes.
The tourists were officially billed as the English Rugby Football Team, however the fact they were captained by a Scot in Bill Maclagan and contained three other players from north of the border, they were tagged as a British Isle team.
The British Isles squad returned to South Africa in 1896, winning 20 of their 21 matches, with the squad containing a number of Irish players for the first time.
The final tour of the 19th Century saw the British Isle head to Australia in 1899, providing their hosts with their first international opponents. The squad was captained and managed by Rev Matthew Mullineux with the Blackheath back one of only only two tour skippers never to be capped by their country.
Having dominated on their previous tours of South Africa, the British and Irish tourists struggled in 1903 - winning just 11 of their 22 matches. The hosts won the Tests series 1-0, with two of the matches drawn.
A year on, the invitation-only squad headed to Australia and New Zealand under the captaincy of Scotland forward David 'Darkie' Bedell-Sivright. The squad dominated the series against Australia winning 3-0, but they lost the 2-0 against New Zealand, with one Test drawn.
In 1908, players from Ireland and Scotland turned down the invitations to play on the tour to Australia and New Zealand - and the England and Wales squad struggled to compete. The squad, playing in red and white hoops, suffered particularly heavy defeats to New Zealand.
Two years later and the British Isles were taking part on two tours - with one squad heading to South Africa and another travelling to Argentina. The squad to face the Pumas was once again classed as English Rugby Union team, however as it contained players from Scotland it billed as the Combined British team by the hosts.
After a long absence due to war, the touring squad was reformed in 1924 to travel to South Africa - with the trip seeing the birth of the Lions nickname. Having travelled as the British Isles Rugby Union Team, the Lions monicker came from the image on their ties.
Now with the emblem of the four Home Unions, the Lions headed to Argentina in 1927 after being invited by the River Plate union. The side - including 11 internationals - played nine matches and were responsible for an upsurge in interest in the sport.
Three years on and the Lions returned to New Zealand and Australia - although they had to approach 100 players to finally get the 29 they wanted for the tour. The Lions won the first Test against New Zealand, but they lost the remaining three and the one-off international in Australia.
The Lions took part in a 10-match tour to Argentina in 1936, with the 23-man squad - including Prince Alexander Obolensky - celebrating a clean sweep on wins. However the tour would be the last time the Lions would travel to the Pumas.
Led by Ireland forward Sam Walker, the Lions went toe-to-toe with the Springboks in 1938. Having beaten Australia and New Zealand, South Africa had collected the tag of unofficial world champions - however the tourists gave them a real test before losing the series 2-1.
Results might not quite gone their way in the first post-war tour in 1950, however the Lions - now playing in red jerseys - won praise for their attacking rugby. They lost the series to New Zealand 3-0, with one Test drawn, but rallied to beat Australia 2-0.
The 1955 squad took the popularity of the Lions to new heights on and off the pitch. Playing an free-flowing brand of rugby - prompted by Cliff Morgan - teenage winger Tony O'Reilly scored 16 tries, while the Test series finished all square. The first Test, a 23-22 win for the Lions, is up there with the greatest matches ever played.
The Lions maintained its attacking philosophy in Australia, New Zealand and Canada four years later - with O'Reilly crossing for 22 tries and Peter Jackson scoring 19 times. Having won the series against Australia, they were edged out by the All Blacks 3-1 - with Don Clarke kicking a then world record six penalties to deny them 18-17 in the deciding rubber.