Objects that can be identified unambiguously as quipus first appear in the archaeological record in the first millennium AD. They subsequently played a key part in the administration of the Kingdom of Cusco and later Tawantinsuyu, the empire controlled by the Inca ethnic group, flourishing across the Andes from c. 1100 to 1532 AD. As the region was subsumed under the invading Spanish Empire, the use of the quipu faded from use, to be replaced by European writing and numeral systems.