Muggles' Guide to Harry Potter/Characters/Nott

Overview
Nott is a Death Eater, whose son Theodore is a Slytherin in Harry's year. He is never given a first name.

Goblet of Fire
Nott is first seen as one of the Death Eaters to appear after Lord Voldemort's re-embodiment. He tried to profess his loyalty to Voldemort before being interrupted.

Order of the Phoenix
Nott is injured in the first skirmish in the battle at the Ministry, presumably by falling shelves, to the extent that Lucius Malfoy instructs the other Death Eaters there present to leave him. It's likely that he did not take part in the final battle (in the Room of the Veil) due to his injuries. He was presumably sent to Azkaban afterwards along with the other Death Eaters who had been captured in that battle by the Order of the Phoenix.

Half-Blood Prince
Nott is mentioned at the beginning of the book by Blaise Zabini. Apparently he was an old friend and ex-student of Professor Slughorn's, however his son was not invited to the Slug Club due to Nott Sr's recent arrest, apparently Slughorn does not wish to have any association with the Death Eaters.

When Lord Voldemort, or Tom Riddle as he is then known, is seen in Albus Dumbledore's memories returning to Hogwarts to apply for the job of teacher of Defence Against the Dark Arts, Dumbledore asks him about his "friends" waiting for him in Hogsmeade. Nott is one of the friends mentioned by name, along with Mulciber, Antonin Dolohov, and Evan Rosier.

Outside the series
Nott originally had a scene in which he and Lucius Malfoy discussed Death Eater business off camera, while their sons Theodore Nott and Draco Malfoy discussed Harry and Albus Dumbledore. The author mentions that while she tried to fit the scene into two different books, it didn't work well either place and so was laid to rest.

Analysis
Nott was one of Lord Voldemort's earliest followers, along with Avery, Lestrange, Rosier, Mulciber, and Dolohov. Unlike the others (with the possible exception of Dolohov) Nott seems to be the only one of the original Death Eaters who are still fighting for Voldemort. The others seem to have been replaced by their sons (or other relatives). It's possible that the Nott we see is also a descendant of the original Nott, though this is unlikely as Harry refers to him as "stooped," generally a descriptions that applies to elders. Additionally, in interviews following the release of the series, JK Rowling has described him as "an elderly widower" when he had Theodore (who is Harry's age). Due to this it's possible that Nott is the longest serving follower of Voldemort's who still serves him today, or at least of the Death Eaters that we've seen.

Greater Picture
Seeing as his son was originally supposed to have a larger role in the series, it's possible that the elder Nott was going to have a slightly larger role too. At the very least he was supposed to appear in a discarded scene involving his son and Draco Malfoy where he would have arrived at Malfoy Manor to discuss Death Eater affairs with Lucius.