The title Baron Latimer or Latymer has been created, by the definitions of modern peerage law, four times in the Peerage of England. Of these, one was restored from abeyance in 1913; one is forfeit; the other two are dormant, although their heir is well known.
All of these, and the title of Viscount Latimer, belong to the descendants of the same medieval family, whose surname was Latimer (Latiner or "translator"); the fourteenth century form of the name should therefore be le Latimer, but it is often found as de Latimer as though it were a placename.
The arms of Latimer appear originally to have been Gules, a cross patonce or. The stems of a cross patonce should expand, as a cross pattée, then terminate more or less like a cross flory. The earliest surviving representation is on the seal of William Latimer, 1st Baron Latimer (died 1305), affixed to the Barons' Letter of 1301 to the Pope.
The arms of William le Latimer were blazoned in Franco-Norman verse by the heralds in the Caerlaverock Roll of Arms made in Scotland during the Siege of Caerlaverock in 1300 as follows:
The term "patee" in this verse of the poem should not be interpreted as paty, or pattée, but rather as patonce. His cross patonce is also displayed in a contemporary stained glass window in Dorchester Church.
In the blazons of the Latimer arms in subsequent rolls the cross is blazoned as patee and patey, though in later times as cross patonce:
The late-medieval heraldic Angevin French terms patee and patey were incorrectly considered equivalent to the 18th century heraldic English patée by most heralds of the 19th century, supposing an early variance in the family arms. But throughout the 14th century the arms consistently displayed Gules, a cross patonce or. One 19th century archivist incorrectly described the cross patonce of William Latimer, 4th Baron Latimer, as a cross flory.
By modern law the existence of a barony by writ requires three things: a (recorded) writ, evidence that the recipient of the writ actually sat in Parliament, and that the Parliament meets the modern legal definition by including representatives of the shires or towns. The oldest writs for the Latimers date from 1299, although the first Baron Latimer also sat in the Parliament of 1290.