The lack of overt inflectional markings encoding finiteness is a crucial difference between Present Day English (PDE) and modern Mainland Scandinavian languages (MSc). In contrast to previous analyses, our approach considers finiteness a primitive distinction explicitly expressed in verbal forms and, crucially, cutting across tense, mood, and agreement markings. Middle English (ME), like MSc, encoded finiteness. MSc languages have retained the encoding of the finiteness distinction in spite of the loss of mood and agreement markings, but PDE main verbs have lost this distinction (although they have tense and agreement markings). This loss leads to a range of syntactic differences between MSc and PDE, such as <i>do</i>-support, different auxiliary-main verb splits, and the lack of V2 in PDE.