Former New York Cosmos president Clive Toye called the league "a magnificent success that eventually failed as a single entity.

The NPSL did not receive sanctioning by the USSFA, as it refused to pay the $25,000 fee, was branded an outlawed entity by FIFA, and players faced penalties for signing with it.

[7] While the USA had FIFA sanction, the foreign teams that were rebranded with American names for the summer 1967 season viewed the league as little more than a training exercise for their off-season, and most did not field their best players.

[10] The expenses of high salaries for foreign players and renting of large stadiums, coupled with low attendances, resulted in every team losing money in 1968, and investors quickly pulled the plug after their year's commitment ended.

[11] The Dallas Tornado won the title after a number of multiple overtime playoff games, including a 173-minute marathon against Rochester.

On September 3, 1973, Sports Illustrated featured a soccer player on its cover for the first time – Philadelphia Atoms goalkeeper Bob Rigby.

[16] SI profiled the Philadelphia Atoms' victory in the NASL championship, the first time an American expansion sports team won a title in its first season.

[17] The 1974 NASL Championship game between the Los Angeles Aztecs and the Miami Toros was televised live on CBS, the first national broadcast of a pro soccer match in the United States since 1968.

The 1975 season saw the signing of internationally known players, including Portuguese star Eusébio to Boston,[20] and former England goalkeeper Peter Bonetti to St. Louis.

In 1975, the New York Cosmos created a media sensation and overnight transformed the fortunes of soccer in the United States by signing Pelé.

From the moment he signed his contract at the 21 Club on June 10, 1975, in front of a crush of ecstatic worldwide media, Pelé's every move was followed, bringing attention and credibility to soccer in America.

Ten million people tuned in to watch CBS' live broadcast of Pelé's debut match—a record American TV audience for soccer—with the Cosmos on June 15, 1975, against the Dallas Tornado at Downing Stadium in New York.

[9] The NASL was shown on the TVS network (a syndicated television service) during 1977 and 1978, although some games were tape delayed or not carried in certain markets.

NASL had been trying to persuade Best to move to America and place him in a major media market, but once the New York Cosmos had signed Pelé, Los Angeles was the logical placement for Best.

[21] Best was traded to the Fort Lauderdale Strikers (a club based in the Miami area) in 1978, and in 1979 Los Angeles signed its next big star, Johan Cruyff.

[23] The Minnesota Kicks were established in 1976 and quickly became one of the league's more popular teams, drawing an average attendance of 23,120 fans per game in 1976 to the Metropolitan Stadium in a Minneapolis-Saint Paul suburb.

San Diego Sockers President Jack Daley later described NASL's boom years of the late 1970s: "It became fashionable to chase the Cosmos.

[33] An apparent era of stability seemed to have arrived, with the 1980 season expecting no planned expansion, relocations or failed teams among its 24 franchises, and with most rosters remaining relatively stable.

[38] Owners spent millions on aging stars to try to match the success of the Cosmos and lost significant amounts of money in doing so.

Phil Woosnam, who had served as NASL Commissioner since 1969 and had been a strong proponent of expansion during the 1970s, was removed by the league's 14 owners in April 1982 by a reported 11–3 vote.

[43] Of those final nine teams, the Chicago Sting, Minnesota Strikers, New York Cosmos, and San Diego Sockers joined the Major Indoor Soccer League for its 1984–85 season.

[47] Canada fared better, coming a win short of qualification for the 1982 World Cup with a squad exclusively made up of NASL players.

Four other well known names (New York Cosmos, Tampa Bay Rowdies, Fort Lauderdale Strikers, and Tulsa Roughnecks) have resurfaced in the new NASL and the USL, which are both Division II leagues.

Two of the oldest derbies in North American professional soccer (Cascadia Cup and Fort Lauderdale–Tampa Bay) began in the NASL of the 1970s, and continue today via successor clubs.

[50] After a couple of years of experimenting, including a three-city tour by the Red Army team from Moscow in 1974, the league again staged tournaments in 1975 and 1976.

Four other teams (Fort Lauderdale, Montreal, Tampa Bay and Tulsa) competed in a short NASL Grand Prix of Indoor Soccer Tournament in early 1983.

The trend started early as players such as Vavá, Peter McParland, Rubén Marino Navarro, Co Prins and Juan Santisteban appeared in the league in 1968.

In addition, several players went on to greater acclaim after leaving the NASL, among them Peter Beardsley, Bruce Grobbelaar, Julio César Romero, Hugo Sánchez and Graeme Souness.

Two players appeared in both the NASL and MLS, spanning a 12-year gap in North American professional soccer: Hugo Sánchez and Roy Wegerle.

Of the 107 games involving NASL clubs that have drawn 40,000+ fans, 65 were Cosmos' home matches at Giants Stadium (excludes Soccer Bowl '78).