Yeoman.

A `gateway ancestor' of many Montagu/es. Wagner provides a good summary:

`The explanation of a fifteenth century yeoman's Norman name might sometimes be female descent from a knightly house through a coheir. The Montagus of Boughton, Northhamptonshire, who acquired a barony in 1621, an earldom in 1689, the dukedom of Montagu in 1705, and in their younger branches the earldom of Manchester in 1626, the dukedom of Manchester in 1719, and the earldom of Sandwich in 1660, descended from Richard Montagu alias Ladde, a yeoman or husbandman, living in 1471 at Hanging Houghton, Northamptonshire, where the Laddes had been tenants since the fourteenth century. Alias names, in some respect the forerunners of modern compound (or double-barreled) name, were common in the Middle Ages. In the earliest times, when surnames were new, an alias may just mean indecision between equally attractive alternatives. Later they sometimes indicate bastardy (one name perhaps being the father's and one the mother's), but in most cases probably mark inheritance through an heiress whose name was thus perpetuated. A good case has been made out for the possibility that the Ladde alias came from a division among coheirs about 1420 of the remaining small inheritance of a line of Montagus at Spratton and Little Creton, also in Northamptonshire. This line was of knightly origin and probably a branch of the baronial Montagus (Earls of Salisbury from 1337), whose almost certain ancestor Dru de Montagud was a tenant-in-chief in 1086. Other yeoman Montagus are found in Buckinghamshire from 1354 when Roger Montagu appears as a witness to a quitclaim of land in Great Kimble, notably in Halton where a family of Montagu alias Elot held land from about 1440 to 1610. A line of Montagus found in Waddesdon from about 1540 may have branched from these. These in the eighteenth century were shepherds and drovers and one set up in Aylesbury as a wheelwright and another as a tailor. Another line, also possibly branched from Halton, is found at Boveney and Dorney in the sixteenth and seventeenth centuries. This produced Richard Montagu, Bishop of Chichester (1628-38) and Norwich (1638-41), and Peter Montagu, who settled in Virginia.' (Wagner).

A franklin was the original name for a free tenant. In England, franklins came to be called yeomen.

Sources:
English Genealogy, Anthony Wagner.

http://www.montaguemillennium.com/familyresearch/h_1471_richard.htm