Diminutive of Montgomery, from Norman French meaning 'Gomeric's mountain.'
Montie is a warm, informal variant of Monty — itself a familiar form of Montgomery, a place-name of Old French and Old English descent meaning "Gomer's hill" or "hill of the powerful man." The Montgomeries were a noble Norman family who carried the name from France to Britain after 1066, and from there it spread across the English-speaking world as both a surname and, eventually, a given name worn without ceremony or pretension. The -ie spelling softens what might otherwise feel like a general's name, and generals there were: Field Marshal Bernard Law Montgomery, known to the Allies simply as "Monty," was one of the defining commanders of the Second World War.
His nickname became so famous that the name itself carries a faint air of capable, no-nonsense authority. On the other side of the ledger sits Monty Python, the British comedy troupe that gave the name a mischievous, absurdist gleam it has never entirely shaken. Montie as a standalone name — rather than a nickname — gives a child something genuinely rare.
It has the feel of a name passed down through a family, worn smooth by use, belonging to someone who tells good stories. In an era of maximalist names and maximalist spellings, Montie's gentle quirk is its own quiet statement.