Before settling in New London, Waller lived in Salem (Massachusetts Bay Colony) and Providence Plantations.

In 1648 he appeared as a witness against a group of men who fired weapons "in jest," which caused the town to sound the alarm warning of an attack.

[13] In the same year he was appointed as an arbitrator with John Throckmorton for a trial against Edward Manton who was accused by Adonijah Morrice of "breach of covenant.

"[14] In 1649 he and Throckmorton were arbitrators for a trial to settle a dispute between William Harris and Richard Chasmore regarding payment for cattle.

[14] Also in 1649, he served on a jury for the trial of Nanheggen of Pawtuxet, a Native American who was accused of burgling the home of Jane Sayes.

[20][21] In the same year he purchased a fifty-acre lot of meadowland lying northwest of town on the Woonasquatucket River in what would become Smithfield.

[22] Historian Michael Cavanagh writes:1662 Providence forms a committee to lay out a new town on lands near Wayunkeke Hill freed up by the 7 Mile Line sale.

William Hawkins and John Steere were granted 50 acres each provided they built houses, cut hay and lived there for 3 years.

Roger Williams, Thomas Olney and son and Mathew Waller were other buyers of 50 acre lots.

[26]In 1650, the prayer in the postscript of this letter was fulfilled: Waller was among the six men John Winthrop Jr. hired to build the town's first mill.

[33] "Matthew Waller aged about 63, dyed very suddainly, none at yt time in ye room wth him.