1908 - 1920

The first era saw Souths dominate the early seasons, before Easts took three titles in a row (1911-13). However, by the end of the decade the most powerful club was Balmain who, apart from 1918, won every premiership from 1915 to 1920. Cumberland and Newcastle clubs were gone by 1910, the year that Annandale started. However, while 1920 saw the arrival of Sydney University, by seasons end The Dales were defunct.

1921 - 1930

The decade began with North Sydney's only golden era that saw them win back to back titles in 1921-22. The opening season also saw the arrival of one of the game's greatest ever clubs - St. George. However, it would be South Sydney who would produce the most successful premiership run yet seen. After finishing as equal first in 1923 and 1924 the Rabbitohs lost both Finals to finish as runners-up (to Easts and Balmain respectively), before they unleashed an avalanche of titles winning every season from 1925 to 1929. Before the next season foundation club Glebe was expelled. At the close of 1930 Wests had secured their first title.

1931 - 1940

Souths regained top spot in 1931 and 32, making it seven titles out of the last eight for the Rabbitohs. Newtown and Wests took their second titles in 1933 and 1934 respectively, however in both seasons a rising Easts side looked to be improving rapidly. The Tri-colours took four of the next six titles on offer - they were arguably one of the best club sides of the century. Amidst Easts domination a newly arrived Canterbury (1935) were smashed 87-7. Yet only four seasons later (1938) the Berries defeated Easts to win their first title. University withdrew from the scene in the same season. In 1939 Balmain grabbed another premiership to improve to seven titles. Fittingly perhaps, the great Easts side of the 1930s closed the decade with a final title.

1941 - 1950

The seasons during WW2 produced large crowds and entertaining football - the first half of the decade saw five different clubs take the premiership. St.George achieved their first two titles (1941 & 49), while Norths made their only ever Grand Final appearance in 1943 before losing to Newtown. Balmain made the most of the 1940s by appearing in five consecutive premiership-deciders, winning three of them. Manly and Parramatta entered the League in 1947 to boost the club numbers to ten, although both struggled early. Wests took their third title in 1948, before the end of decade saw South Sydney on the rise again. The Rabbitohs finished as runners-up in 1949, then went one better in 1950 by defeating Wests in the Final.

1951 - 1960

Apart from Wests in 1952, honours for the decade were shared solely between magnificent South Sydney and St.George sides. The Rabbitohs had an astounding run from 1949 to 1955, making all seven deciders and winning five of them. Newtown finished as minor premiers in 1954 and 1955, but fell to Souths both times. Meanwhile Manly made three Grand Finals, but their inexperience told. Come 1956, no one forsaw what was to eventuate as St.George rose from being a regular Top 3 club into an unbeatable machine. In a title-run that would eventually span 11 seasons, St.George took every premiership of the decade from 1956 onwards. Many clubs rose to challenge them, but when the results mattered the Saints produced the goods.

1961 - 1970

St.George opened the decade facing its most difficult opponent in Western Suburbs. The Magpies had more Test players, yet in close battles in 1961, 1962 and 1963 St. George conjured victories to utterly frustrate Wests. The Saints dismissed Balmain's 1964 challenge before in 1965, a crowd of over 78,000 packed the SCG to see a young Rabbitohs side push St.George to the limit, yet the Dragons held on. Balmain came again, unsuccessfully, in 1966 as St.George made it 11 titles straight. Penrith and Cronulla entered the fray in 1967 as Canterbury ended the Dragons run in the Final, but fell themselves to Souths in the decider. For Souths, it was the first of five straight Grand Finals. They beat Manly in '68 & '70, however were upset by Balmain in 1969.

1971 - 1980

Souths took their twentieth title over perrenial runners-up Manly in 1971. However, by the end of the decade the Sea Eagles would have four premierships to their name (1972, 1973, 1976 & 1978). A great Easts side appeared in 1974 and 1975 to take back to back titles, including a white-wash of St.George. The Dragons though came back again with a young side to take the 1977 and 1979 Grand Finals, to raise their tally to fifteen titles. While the young Cronulla club made an impression by making two Grand Finals, the second half of the decade saw the rise of Parramatta and Canterbury (the latter taking the 1980 premiership). The 1977 and 1978 seasons were also memorable as they both featured drawn Grand Finals and the need for replays.

1981 - 1990

Parramatta swept all before them as they won their initial titles in 1981, 1982 & 1983. By the end of that run, their 1981 opponents Newtown were out of the League, while Illawarra and Canberra expanded the competition outside of Sydney. Canterbury won back to back titles in 1984 & 1985 before the power clubs of the decade met each other in the 1986 Grand Final where the Eels won a tryless tussle. Manly took the 1987 title over an unexpected opponent in Canberra. Brisbane, Newcastle and the Gold Coast joined for 1988 as foundation club Balmain fell to Canterbury. Balmain were defeated again in 1989 by Canberra in extra-time. After winning their maiden premiership the Raiders returned in 1990 to defeat first time Grand Finalists Penrith.

1991 - 2000

Penrith secured their maiden title in 1991, before Brisbane began with a double (92/93). Turmoil though ensued as clubs came and went. 1995 saw the arrival of Nth Qld, Sth Qld, Auckland and Perth, before the Super League arrived in 1997 with the Hunter and Adelaide sides. The formation of the NRL saw the entry of Melbourne and end of the Mariners, Perth, Rams, Crushers and Gold Coast. Joint-ventures, finances and exclusions then brought about the end of Norths, Wests, Balmain, Illawarra, St.George and seemingly Souths and Manly. In their place were St.George-Illawarra, Wests Tigers and Northern Eagles. On the field the Brisbane club dominated the period with a powerful side.

2001 - 2006

Parramatta dominated all-comers in 2001 but fell in the Grand Final to an Andrew Johns led Newcastle side. The Northern Eagles venture came and went, while South Sydney were reinstated. The 2002 premiership marked the long awaited rise of the New Zealand Warriors as they won the Minor Premiership and reached the Grand Final. Meanwhile Canterbury were dropped to last place after an elaborate salary cap scheme was uncovered. The Sydney (Easts) Roosters won their first premiership since 1975. In 2003 the Penrith Panthers, wooden-spooners two seasons earlier, stunned almost everyone by reaching and winning the Grand Final. Canterbury recovered to reach the 2004 Grand Final against the Roosters. Despite the experience of having played in three of the last four deciders, the Sydney Roosters could not stop the Bulldogs. Wests Tigers surprised all in the NRL in 2005 by winning in their first appearance in the play-offs. Between 1999 and 2005, seven different clubs won the premiership. In 2006 Brisbane out-pointed the Melbourne Storm in a controversial match, which was also the first ever "non-Sydney" decider.