When the speaker of "When I was One-and-Twenty" announces his age in the first line of this poem, you know that it's important. And hey – maybe the journey from 21 to 22 is life-changing enough for him to be able to say that he's moved from youthful idealism into grown-up…cynicism? We're not saying that 21 is a young age – but, in our speaker's case, it's a past that's so long ago he can barely remember what it felt like. What a difference a year makes, huh?
This poem is a classic example of an older person looking back at the follies of their youth.
At the end of this poem, the speaker is just as young and naïve as he was when the poem began.