Pagan's Crusade is the first in a series of young adult novels by Catherine Jinks. It might best be described as a historical war story, being the story of a young man who finds himself fighting in the crusades. It is somewhat humorous, depending on how amusing you find the complaining of the protagonist. And it is surprisingly popular.
This is a rather unusual story, in that it seems rather directionless, and a lot of the early potential subplots go nowhere. While I called it 'historical', it isn't overly focused on the ways of medieval life. While it is technically an adventure, it starts of very slow, and takes forever to build up the action. It is not a traditional survive-against-all-odds story, nor the somewhat less-traditional sorry-sap everything-happens-to-me story, but is certainly a story of living in bad times surrounded by bad people. Including, to some extent, the main character.
Pagan Kidrouk is an orphan, raised in a monastery from an early age. He ran away when the beatings grew too severe, and has been making his own way in the backstreets of medieval Jerusalem ever since. He has managed to work his way up, however, and after a stint in the city watch he is looking for more pleasant employment with the Knights Templar. He secures a position as a squire, and then nothing much happens. He helps herd stupid and silly pilgrims through the holy sites, he gets into a fight or two, and he complains a lot. But the story pretty much fails to take off.
Pagan is some what silly, and very sardonic and cynical. Most of all, he is a royal smart mouth, at least in his own head, and we get to hear all of the snarky comments that he doesn't say out loud. Perhaps that is enough to earn it its current popularity in the eyes of today's youth... But it may also be that towards the end the book gets more exciting, and gruesome. It's rather hardcore by the standards of the YA section. I was somewhat surprised to see it recommended for children as young as nine; while it is probably not going to scar anyone for life, it's a bit more dramatic than anything I wanted to read at nine. I'd recommend it for the 13-and-up crowd, and quite frankly, I'm not actually going to recommend it to anyone -- there are much better books out there.
Pagan's Crusade came out in 1992, with the series finally completing in 2006. This prolonged run may be part of the reason why the series remains reasonably popular with kids and teens (although it is nowhere near as popular as Harry Potter or Twilight; I would guess that it approaches Artimis Fowl in popularity.) I suspect that once new books stop coming out every few years the series will sink into obscurity, but I may be wrong; there are a surprising number of fans of all ages, and worse books than these have managed to stay popular for decades...
The Pagan Chronicles appear to be complete, and include a total of four books: