Some time secretary to Lord Emsworth at Blandings Castle and much admired for his efficiency and devotion by his Lordship's sister, Lady Constance (and even by Lord E. initially).
He has also been secretary to an American millionaire, Mr Horace Jevons, to whose employment he returned after being sacked by his Lordship. Despite this, Baxter looks on Blandings as his spiritual home and visits from time to time, much to the annoyance of his Lordship. He was previously employed by Sir Ralph Dillingworth, a Yorkshire Baronet, and later worked for the Duke of Dunstable - he appears to be working his way up the aristocracy.
Baxter suspects . . . . everyone.
Still secretary, he immediately suspected Psmith, when he arrived at the Castle under the name McTodd. Woken up at night by another guest trying to retrieve a stolen diamond necklace, he got locked out and tried to attract his Lordship's attention. Unfortunately, he chose to do it with flower-pots. (Leave it to Psmith)
In the play version, he had a shorter, more restrained role and a habit of resigning only to be dissuaded by his employer - Lord Middlewick, not Emsworth. (Leave it to Psmith play.)
He was invited back to Blandings by Lady Constance to steal Galahad's Reminiscences. While there, he fell for Sue Brown, fell out of a window and went pig hunting. (Summer Lightning)
He returned, after leaving Mr Jevons who was returning to the States, to become tutor to Lord Emsworth's grandson George. After several incidents at the wrong end of an airgun, he left Blandings once more. (The Crime Wave at Blandings)
He was employed as secretary to the Duke of Dunstable to help write his family history and accompanied him to Blandings. Here he detected impostors with his usual efficiency and was backed up by his admirer, Lady Constance. He was assaulted by the Duke with an egg for singing the 'Bonny, Bonny Banks of Loch Lomond' and last seen sleeping soundly. (Uncle Fred in the Springtime)