House Plumm is a noble house of the Westerlands. Neither their arms or their motto appear in the books. According to semi-canon sources, they blazon their arms as three purple rondels on gold. Their words are "Come Try Me."
Seat: The Runefort
The Plumms call their seat the Runefort. It was built by the First Men and it is said that their runes can still be seen carved into the stone in the oldest parts of the castle. It is built on a high hill at the foot of which lies the village of Plumbridge. Though it was once a true military fortress, it has in the last few centuries been expanded with the thought of luxury instead of defensibility in mind.
Prior to the First Era
The Plumms are a house of First Men origin from the Age of Heroes.
The aged Lord Ossifer Plumm married Princess Elaena Targaryen in 176 AC, during the reign of King Aegon IV Targaryen. He is said to have died during the bedding, after conceiving a son. However, rumors suggest that Lord Ossifer had died before being able to consummate the marriage, and that the child instead had been fathered by King Aegon himself, leading to the saying that Ossifer had had a "cock six foot long".
Regardless of the true paternity of the child, Elaena's son, Viserys Plumm, inherited Ossifer's lands and titles. Viserys ruled throughout the reign of King Daeron II Targaryen, and still ruled during the early years of the reign of King Aerys I Targaryen, at least.
Ser Maynard Plumm was among the hedge knights gathered by a lake on their way to Lord Ambrose Butterwell's wedding festivities in 211 AC. Maynard assisted Ser Duncan the Tall during the Whitewalls tourney, but he went mysteriously missing when the Second Blackfyre Rebellion was quashed.
House Plumm fought for House Lannister in the Ascent of the Lion.
House Plumm committed soldiers to fight in the War of the False King, though considerably less than during the Ascent. Lord Ossifer was also absent, instead relegating command of the Plumm forces to his oldest son, Ser Philip.