In this paper, based on quantitative evidence collected on YCOE, I first distinguish various types of pre-nominal genitives in Old English. I then try to reduce a series of changes that affected the syntax of the adnominal genitive to a single primitive, focusing on the causal mechanisms of syntactic change. I examine the different ways in which one change, namely the loss of post-nominal inflected genitives in Old English, can be the direct cause of further changes, or crucially contribute to making them possible. In particular I discuss: (1) the loss of N-raising, which I argue did take place in Old English and was lost when the crucial triggering evidence (i.e. post-nominal external arguments of the noun) was lost; (2) the morphological re-analysis of the genitive inflectional marking as a phrasal affix, made possible by the loss of post-nominal genitives, which, not being subject to ‘splitting’ would otherwise have provided crucial evidence against re-analysis. (3) the replacement of inflected genitives by of-phrases, which became necessary when the use of a pre-nominal genitive instead of the then obsolescent post-nominal inflected one would have conveyed the wrong meaning.