Unlike his elder brothers Edward and Henry, Montagu does not seem to have been academically inclined, and instead of being given a formal education pursued a military career from an early age. The recipient of an Irish pension by 1586,
Montagu’s younger brother James became bishop of Winchester in 1616 and shortly afterwards appointed him keeper of Farnham park.
Montagu was on firmer ground in the debate on foreign trade on 26 Feb., when he pointed out that the influx of Spanish silver had fundamentally altered relative prices of gold and silver, as an underlying cause of inflation. The following day he maintained that England had an adverse balance of trade with the Low Countries.
Montagu may already have been conscious of declining health when he drew up his will on his 57th birthday in January 1624.
On 28 Feb. 1625 Montagu was named with Sir Nathaniel Rich* to a commission to inquire into an imposition on tobacco in the Somers Islands, intended to pay for the maintenance of a minister there; but he did not live to complete his report.
