which came first

[cacian]

small cases or capital letters?

[Maximilianus]

If I'm correct, the first attested use of our modern alphabet can be attributed to the Romans. As far as I have seen, their surviving documents are written in capitals. This assumption may be inaccurate though, since I'm no expert in the history of writing.

[OrphanPip]

According to wikipedia lower case lettering emerged somewhere between 300-800 AD for the Latin alphabet.