Get out the microscope, because we’re going through this poem line-by-line.
"It chanced upon a day that Launcelot came
To dwell at Arthur's court: at Christmas-time
This happened; when the heralds sung his name,
"Son of King Ban of Benwick, seemed to chime
Along with all the bells that rang that day,
O'er the white roofs, with little change of rhyme.
- The still-unnamed woman begins to speak again.
- She says that Launcelot came to Arthur's court at Christmas one year – she doesn't say exactly when, though.
- She makes it all sound very accidental: Launcelot "chanced" to come to Arthur's court.
- The heralds, the guys who announce the arrival of important folks to the castle, shouted that the "Son of King Ban of Benwick" (a.k.a. Launcelot) had arrived.
- The speaker says that their announcement seemed to go well with the bells that were chiming all day for Christmas.
- We're left to guess exactly what that means. Maybe she means that it seemed like Launcelot just belonged there, but she doesn't elaborate or explain.