'freely-allowed' is a modern English compound formed from 'freely' and 'allowed'. 'Freely' comes from 'free' plus the adverbial suffix '-ly' (Old English), and 'allow' comes into English via Old French 'alouer' (see below).

'free' comes from Old English 'frēo' meaning 'not enslaved, free'; the adverbial suffix '-ly' comes from Old English '-līc' (making adjectives/adverbs). 'Allow' entered English from Old French 'alouer' (to approve, permit), itself influenced by Latin elements (see meaning change). These parts combined in Modern English to form the compound 'freely-allowed' to describe something permitted without restriction.

Originally the components meant 'free' (not confined) and 'allow' (to give permission or approve). Over time, combined as 'freely-allowed' it conveys the current meaning 'permitted without restriction'.