The medieval merchant republic

[Grenzer]

What was the class nature of these states? Also if anyone knew of any Marxist or left-wing literature on the subject, that would be helpful as well.

[Questionable]

http://www.marxists.org/archive/kautsky/1888/more/index.htm

Something like that is all I can think of at the moment. Sorry if it's not quite what you had in mind.

[Astarte]

What was the class nature of these states? Also if anyone knew of any Marxist or left-wing literature on the subject, that would be helpful as well.

These were what was known as "Pre-Capitalist", or proto-bourgeois economic formations - essentially they engaged in accumulation of capital, but rather through the mechanisms of petty trade as the hegemonic mode, instead of the exploitation of wage labor as in modern capitalism. I would recommend "Pre-Capitalist Economic Formations" by Marx. I would say the class nature of such trade cities were that of a nascent bourgeoisie forming in embryo against the backdrop of European feudalism - meaning they had a very precarious existence and were at the mercy of various feudal powers.

[Blake's Baby]

I think one of the problems in categorising them is we use the term 'capitalism' very losely, and very specifically, and it's not always clear which we're using.

They were capitalist; mercantile capitalist, not industrial capitalist (though there was some 'industrialisation' going on, the first experiments in the factory system were in Italy in the 1200s, I believe). Their economies were a mixture of simple commodity production (artisan/peasant production) and production through wage labour. Already you can see the interpenetration of the rising bourgeoisie with the feudal aristocracy.

No recommendations for literature, sorry. That's a slice of pure theoretical reasoning. But anything on late-medieval or early-modern political, economic and social developments is worth reading and mining. I recommend reading up on the 100-Years-War as a particularly interesting period of state-formation and capital development in this period, which might provide a counterpoint to any info you get from say Italy.