"By Gryffindor, the bravest were
Prized far beyond the rest."
-- Sorting Hat (GF12)
Godric Gryffindor was the founder of Gryffindor House and one of the co-founders of Hogwarts, described as one of “the four greatest witches and wizards of the age” (along with the other three founders) (CS9).
He believed that anyone who showed magical ability should be allowed to attend Hogwarts, although he favoured the daring and courageous. He was the most accomplished dueller of his time. Through his life, he fought against Muggle-discrimination (JKR).
According to the Sorting Hat, Gryffindor came "from wild moor" (GF12). Bathilda Bagshot's A History of Magic is a little more specific: Gryffindor was born in the West Country village of Godric's Hollow, named for Godric himself (DH16).
The Sorting Hat originally belonged to Gryffindor (GF12). His goblin-made sword, with rubies in the handle, has also survived and was, at various times, in the possession of Dumbledore, Harry, Ron and Neville. The sword was not stolen from the goblins, though they feel otherwise (DH25, BLC).
Colors: Red and gold.
Duelling, teaching and campaigning for an end to discrimination against Muggles.
JKR's "Wizard of the Month" for July 2007.
Based upon the image by Lightmaker from JKR's website (shown here), he has mane-like red hair, green eyes, and a powerful build. Canon, or artistic license? Only Jo (and Lightmaker) know for sure.
As noted above, the Sorting Hat let us know that Gryffindor was "from wild moor." Commentors on the Mugglenet Alohomora! podcast noted that this particular origin point reflects the "wild" or adventurous spirit of Godric and the students of his house. We might imagine Godric adventuring over the wild moors near Godric's Hollow during his youth before he set out for Hogwarts. --Hufflepuffskein
On Episode 32 of the Mugglenet Academia podcast, John Granger and guests discussed an interesting fact about St. Godric from the Christian tradition which may have influenced JKR. St. Godric's familiar is a white stag. Connections to James and Harry Potter's stag patronus are intriguing.