A student thoughtful about etymology asked about this formation in English, after seeing the word fragmentum used by Virgil (Georgics IV.304). Another she had come across was fundamentum (Pro Milone 27.75). But after some thought, she had realised, partly by virtue of a sensitive ear, that not all our –ment words come direct from Latin: many of them sound like French.
She was right. There are at least 400 of such words, but only a minority come direct from Latin, and most are borrowings from—or associated with—French, a language seemingly in love with this formation. Some clear examples are regiment, attachment, reinforcement, disengagement, disillusionment, entrenchment, easement (now a legal word), etc.
In the golden age when an educated person was expected to read French as easily as English (our own Queen’s education came in at the tail end of that), there was continual interchange between the two languages, and a look at the OED reveals that with many of these words it is unclear how and when the borrowings took place.
But there are many also, as the OED points out, that have been ‘formed within English, by derivation’ (i.e. from French or Latin) and some that have been coined from words of Germanic origin, like wonderment and acknowledgement. Some of these words sound deceptively modern, but most perhaps are not. The following are examples, with year of first recorded use in brackets:
redeployment (1941), bedazzlement (1806), readjustment (1749), disarmament (1710), bombardment (1702), settlement (1648), reimbursement (1591), enhancement (1577), impoverishment (1564) disappointment (1551) achievement (1477) payment (1370).
Here again English displays not only versatility but readiness over centuries to accept and adapt words from abroad.