Anarchism does not require an advanced level of capitalism to be established. Or, perhaps, more accurately, anarchy doesn't, some anarchisms might.
Anarchic social relations have existed long before (and continue to in spite of) capitalism. It isn't about a level of economic development or sophistication, because, while anarchism does address economics, it is about much more. Anarchism is, at it's best (and, perhaps, most terrible) looking to destroy the social relations we have come to understand as normal. Social relations which exist with or without advanced levels of capitalism, and also (at least for some of us) a recognition that advanced modes of production without capitalism do not make a better world.