Proteins have long been known to persist inQuaternary bone fossils and are often targetedas a source of carbon used in radiocarbon dat-ing and stable isotope analyses for determin-ing provenance and obtaining dietary informa-tion. We have previously reported a techniqueusing the dominant structural protein collagen(type I) as a source of genetic information forspecies identification in modern and relativelyyoung (Holocene) archaeological samples. Wereport a systematic investigation of amino acidcomposition and collagen peptide mass finger-prints (PMF), for a range of samples datingback approximately 1.5 million years.Extrapolation from high temperature experi-mental decomposition rates predict that at aconstant 10 ̊C (the approximate mean annualair temperature in Britain today) it will takebetween 0.2 and 0.7 Ma for levels of collagen tofall to 1% of their original concentration in anoptimal burial environment. Even when theglacial intervals of the British Quaternary arefactored into the temperature calculations, themore conservative of these two estimatesextends the range for collagen sequencing tothe Lower Pleistocene as confirmed by thepresence of collagen peptides in bones fromthe Weybourne Crag (~1.5 Ma). Collagen fin-gerprinting can extend the range of identifi-able taxa present at sites with large assem-blages of fragmentary bone material such asthat encountered at the ~900 Ka site atHappisburgh (Norfolk, UK) recently identifiedas showing signs of the earliest humans inBritain.