Question

how reliable is archaeology as a source of history

Answer 1

The things archaeologist find are what they are. They are reliable because they are objects. Now, the real problem is the interpretation

Answer 2

archaeology is not about history its about culture and how culture evolves, or rather doesn’t in many cases. What objects and how we use them can tell us about how people related to each other and their environment. For any historical value the results of archaeology must be combined and cross referenced across disciplines. This is because of statistical limitations. You assume any archaeological sample includes approximatley 5 percent of the material that was originally there. Only a percentage of that percentage is reliably “in situ” that is stayed where it was dropped or laid so many years ago, and the sample as a whole is rarely anything but discards, and so diagnostic value unless taken as a body of objects is limited. You take the results of archaeology and overlay them with palentology, bioarchaeology, biology, geology, history, art criticism, and folklore and you can start to see what occured historically, but as with now, the bulk of people that made up any given culture at any given point in time are voiceless as individuals, but that goes into the metaphysics of archaeo and beyond this post.