It's the third Asterix book, i.e. one of the early ones. It's also a bit out of character. It was drawn less than 20 years after the end of World War Two, while Goscinny was Jewish and had lost family members in the Holocaust.
It stars Goths as pseudo-Germans. (This is geographically inaccurate, since the Visigoths were actually from Central Europe.) The book's thus a bit Goth-bashing. Uderzo later apologised for this and showed Goths more sympathetically in later Asterix stories, but I thought the characterisation was fine. The book's problems are:
(a) it only gets funny halfway through
(b) the finale's mean-spirited
The first half is just Asterix, Obelix, Romans and Goths wandering around a forest. Getafix is participating in a druids' convention, but the Goths kidnap him to take back to Germania. Fair enough. They're barbarian marauders in the year 50 BC. Seems reasonable behaviour to me. If anything, they've been kiddified, e.g. when they ambush some Roman soldiers and... tie them up. Uh, right.
The druids are all adorable, by the way. They don't practice human sacrifice or wind human intestines around oak trees.
Anyway, there's a lot of toing and froing. Unfortunately, the Goths at this stage aren't comedy characters. They're just big thugs. The Romans eventually start being funny, although it takes a while. They're very stupid and they get some good lines. "We were outnumbered by two Gauls who took our clothes!"
The book improves when Asterix and Obelix enter Germania, though. The Goths are bureaucratic, eat cabbage and unintentionally demonstrate why it's a bad idea to terrify your interpreter. They also make lots of threats involving torture and executions, but this is in the same book as a Roman general promising to throw his own legionaries to the lions. Asterix and Obelix are as amusingly cheerful as always and you've got to feel sorry for the poor Goth who's guarding their dungeon.
Then comes the ending, though.
Getafix has already been atypically callous. He kept quiet about being able to speak Goth, then eventually used this knowledge to humiliate his interpreter and got him thrown in the dungeons for execution. Admittedly, the interpreter's scummy enough for this to be amusing, but our heroes' next action is to trash the Germanian state. They go around giving magic potion to random Goths and encourage all of them to start a war to become king. Result: centuries of non-stop civil war. Admittedly, Germany was indeed lots of squabbling, disunited principalities until 1871, but it's still odd to see our comedy heroes gratuitously destroy a country before going home.
In all the other books, Getafix is lovely. Here, he's a bit of a bastard. "Yes, but before leaving the country, we must discourage the Goths from invading us... and make sure they stay discouraged!"
Obelix is his usual loud idiot self. He's a fat, jolly man-child who provides a lot of this series's laughs... but I'm also starting to find him mildly sinister. He's really violent. This is a man with super-strength who's happy to punch a helpless captive in the face to threaten him. Also, if you're a wild boar, he's a horror monster.
This book eventually becomes amusing, but it's a long way from being classic Asterix. I do like it, though. It's patchy, but it made me laugh. The hostile portrayal of the Goths is actually fine, especially compared with some of the out-and-out villains in other Asterix books. They're goofy barbarians in a broad comedy comic strip. What's the problem? Also, Uderzo draws some of the best Dingbats Comics Swearing.
"I was attacked from the rear by some Goths who were invading the Goths."