Across the decades, I've noticed a popular tendency to minimize the drummer's accomplishments within the Beatles ensemble.
Perhaps this is because because he wrote the fewest songs and drew the fewest headlines. Here are five factors to take into account before dismissing Richard Starkey, aka Ringo Starr, as "one of history's most charming bit players." (One book on my shelf uses those words!)
1) Starr gave the Beatles something to shoot for when the band was not very good. Only the historians remember it now, but the Beatles were, for some time, playing catch-up to Liverpool's real band, Rory Storm and the Hurricanes. Their drummer? Starr, who reminisces as follows: "I met the Beatles while we were playing in Germany. We'd seen them in Liverpool, but they were a nothing little band then, just putting it together. In fact, they weren't really a band at all." Of the same period, Harrison recalled: "Ringo seemed to us to be cocky. Relative to what we were like at the time, the band he was with were very professional.... (Our manager told us,) 'You'd better pull your socks up because Rory Storm and the Hurricanes are coming in, and you know how good they are. They are going to knock you for six." The two bands played epic all-night sets in competition with each other in Hamburg.
2) The Beatles did not explode until Starr replaced Pete Best. And once he did, the band became a national phenomenon in Britain. To compare the relative drumming skills of each, consult the first Anthology disc. No contest. Before Ringo Starr joined, the Beatles were an interesting local act. After Ringo Starr, they were a national phenomenon. The impeccable backbeat with which he propelled their numbers just happens to have preceded their breakthrough in the UK.
3) Starr was the most popular Beatle in the United States at the time of their breakthrough here. People tend to forget this. In the critical year of 1964, Ringo fans easily outnumbered fans of the other three. Ringo-themed merchandise vastly outsold John-, Paul-, and George-themed merchandise in the US.
4) Starr was the only one of the four capable of holding down the lead role in a film. To be blunt, he was the best, and perhaps the only, actor in the group. Whether or not he was ever going to win an Oscar is beside the point. A Hard Day's Night (the film) consolidated the band's global dominance, and in it, Ringo Starr delivers a charming comic performance. Thus, at yet another critical point in the band's career, Starr took center stage, leaving one to wonder once again what the band's trajectory would have looked like without his contribution. (He repeated the trick in Help!)
5) Alone among the four, he revolutionized his instrument. Steve Smith, best known as the drummer for Journey, may have put it best: "Before Ringo, drum stars were measured by their soloing ability and virtuosity. Ringo's popularity brought forth a new paradigm ... we started to see the drummer as an equal participant in the compositional aspect ... His parts are so signature to the songs that you can listen to a Ringo drum part without the rest of the music and still identify the song."
Ringo was the most important Beatle. I suppose I should say here that I'm assessing Starr's importance to the group's career, not his impact as a songwriter. Regardless -- give the man his due.