Leinster and Ulster finished second and third respectively in the league but Munster walked away with the regular season, losing just three of their 22 games and topping the table by a remarkable 13 points.
The Red Army, coached by Tony McGahan and captained by Paul O'Connell, went on to comfortably down Ulster in their semi-final and then get revenge on rivals Leinster for their 2010 semi-final defeat by beating them in the final for Munster's second Celtic League in three years.
New boys Aironi struggled in their opening Celtic League campaign, winning just once, but their compatriots Benetton Treviso mustered an impressive nine wins to finish tenth in the table - behind Edinburgh and Connacht due to their lack of bonus points.
Early winners:
Reigning champions Ospreys faced a tough challenge in the opening round as they travelled to Ulster.
Tries from Dan Biggar and Richard Fussell were not enough to earn the win as they went down 27-26 in Belfast.
Treviso got off to a fine start in the Celtic League with a 34-28 win over Scarlets and Munster breezed past Aironi.
In fact Munster won their first four games until they came up against Leinster in Round 5 when they came unstuck in Dublin, losing a tight encounter 13-9.
Treviso's fine start to the season continued in Round 3 as they overcame Leinster 29-13, but their Italian compatriots Aironi failed to get a win until Round 18.
Welsh sides had mixed fortunes early in the season with Newport Gwent Dragons winning just once in the first five games, Scarlets and Ospreys each won three, while Cardiff Blues won four.
Glasgow Warriors were struggling with just one win from five while Edinburgh were only one better, although that extra win did come impressively against Leinster.
The run-in:
As the season wore on Munster's dominance of the league only grew, they did suffer two shock losses to Newport Gwent Dragons and Treviso but McGahan's side were clearly the pedigree side in the league.
Munster, Leinster and Ulster has all secured their semi-final spot heading into the final round of games in May 2011 but three of the Welsh regions all entered the final round with eyes on the remaining spot.
Ospreys took on Aironi in Italy but the tie of the round was at Parc y Scarlets as the home side played Cardiff Blues with fourth spot still up for grabs.
Scarlets won a ding-dong battle 38-23 in Wales thanks to two tries from Sean Lamont but the bonus point win was in vain as Ospreys scraped past Aironi 12-10 to snatch the semi-final spot by a single point.
Dragons finished in seventh place with Edinburgh in eighth and the bottom four made up of the Italian debutants, Connacht and Glasgow Warriors.
Aironi's poor showing in the league was a sign of things to come.
The following season they would win four games but it would be the last season they would play in the Celtic League as the Italian Rugby Federation revoked their licence to play.
Play-offs:
Ireland's strength had shone through during the regular season with third-place Ulster finishing four points clear of their closest rivals.
Leinster, captained by current coach Leo Cullen, faced Ulster in Dublin with Rory Best skippering the visitors.
Ulster had shipped at least 30 points in each of the two regular season losses to the Leinstermen and although they limited them to just 18 in the semi-final, the most they could muster was a Ruan Pienaar penalty and they were comprehensively beaten.
Tries from Fergus McFadden and Luke Fitzgerald meant Leinster eased into the final - but who would they play?
The winners of the previous two seasons met at Thomond Park as Munster continued their regular season dominance with a tight win over Ospreys.
A try-double from Danny Barnes and two Ronan O'Gara penalties gave the home side an 18-11 win over the Welsh region as Fussell's try was not enough to stop the Munster-men's seemingly inevitable showdown with Leinster in the final.
Leinster had been crowned European Champions just a week before the final but Munster had been the dominant force in the Celtic League this season and that was not about to change.
With a side boasting Irish rugby giants such as O'Gara, O'Connell, Keith Earls, Donncha O'Callaghan, John Hayes and Marcus Horan - as well as All Black talent Doug Howlett, Munster downed their provincial rivals 19-9 to win their second title in three years.
Howlett and Earls crossed the whitewash either side of half time and a penalty try on 79 minutes sealed the victory for McMahon's men.
Leinster's points all came from the boot of Jonathan Sexton as the European champions failed to break down the Munster defence.
Top Scorers:
Osprey's Biggar topped the point-scoring table with an impressive 248, 24 ahead of his nearest rival Ian Keatley, of Connacht.
It would be a sign of things to come from the then 21-year-old Biggar who, now 26, is already Ospreys leading point scorer in history.
It was a season for young performers as Edinburgh's Tim Visser touched down 14 times despite his side struggling in the lower reaches of the table.
Visser scored two more tries than his nearest rival, Dragons' Aled Brew, to top the try-scoring charts for the second year in succession.
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