William Catesby and Margaret Zouche were married.

William Catesby lampooned in the poem by William Collingbourne: The Catte, the Ratte and Lovell our dogge rulyth all Englande under a hogge.

Around 1435 [his father] William Catesby (age 27) and [his mother] Philippa Bishopston were married at Bishopston, Warwickshire.

Around 1446 [his father] William Catesby (age 38) and Joan Barre were married.

In 1450 William Catesby was born to William Catesby (age 42) and Philippa Bishopston.

In 1470 [his father] William Catesby (age 62) died at Ashby St Ledgers, Northamptonshire.

In 1473 [his son] George Catesby was born to William Catesby (age 23) and Margaret Zouche (age 14) at Ashby St Ledgers, Northamptonshire.

Close Rolls Edward IV Edward V Richard III 1476-1485. 30 Jun 1483 William Catesby (age 33) was appointed Chancellor of the Exchequer. King Richard III of England (age 30). Westminster Palace [Map] Grant for life to William Catesby, esquire, of the office of Baron of the Exchequer, receiving the accustomed fees at the Exchequer or the receipt of the Exchequer, with all rights, profits and commodities. By p.s.

Grafton's Chronicle. [Aug 1483]Kyne Richarde after his coronacion, taking his waye to Glocester, to visite in his newe honour, the towne, of which he bare the name before of old, deuised as he rode to fulfill that thing which he before had entended. And forasmuch as his minde gaue him that his neuewes lyuing, men woulde not recon that he coulde haue right to the realme: he thought therefore without delay to ridde them, as though the killyng of his kynsmen might ende hys cause, and make him a kindly king. Where vpon he sent one Iohn Greene, whome he specially trnsted. vnto Sir Robert Brakenburie, constable of the tower, with a letter and credence also, that the same

Sir Robert in anye wyse shoulde put the two children todeath. This Iohn Greene did his errand to Brakenbury, kneeling before our Ladye, in the Towre, who plainely aunswered that he would neuer put them to death, to die therefore. With y which aunswere Iohn Greene returned, recompting the same to king Richarde at Warwike yet on his iourney, wherwith he toke such displeasure, & thought, that the same night, he sayd, to a secret page of his: Ah, whome shall a man trust? they that I haue brought vp my selfe, they that I went would haue most surely serued me, euen those favle me, & at my commaundement wyll do nothing for me.

Sir quod the page, there lieth one in the palet chambre without, that I dare well say, to do your grace pleasure, the thing were right hard that he would refuse, meanyng this by

Sir Iames Tirrell (age 28), which was a man of right goodly personage, and for the giftes of nature worthy to haue serued a much better Prince, if he had well serued God, & by grace obteyned to haue as much truth and good will, as he had strength and witte. The man had an high hart, and sore longed vpwarde, not risyng yet so fast as he had hoped beyng hindered and kept under by Sir Richard Ratcliffe (age 53), and Sir William Catesby (age 33), which longyng for no more partners of the Princes fauour, namelye not for him, whose pride they knewe woulde beare no pere, kept him in secret driftes out of all secret trust: which thing this page had well marked, and knowen: wherefore, this occasion offered, of very speciall friendship spied his time to set him forward, and in such wise to doe him good, that all the enemies that he had (except the Deuill) coulde neuer haue done him so much hurt and shame, for vpon the Pages wordes, king Richard arose (for this communication had he sitting en a Iaques, a cotmenient carpet for such a counsuyle) and came out into the palet chambre, where he did find in bed the sayd Iames Tyrrell, and

Sir Thomas Tyrrell, of person like, & brethren of blood, but nothing of kinne in condicions. Then sayde the king merely to them, what Sirs, be you in bed so sone? and called up Iames Tyrrel and brake to him secretly his minde, in this mischeuous matter, in the which he founde him nothyng straunge. Wherfore on the morowe he sent him to Brakinburie with a letter by the which he was commaunded to deliuer to the sayd Iames all the keyes of the Towre for that night, to the ende that he might there accomplishe the kings pleasure in such things as he there had geuen him in commaudement. After which letter deliuered and the keyes receyued, Iames appointed the next night ensuing to destroy them, deuisyng before & preparyng the meanes.

On 24 Jan 1484 William Catesby (age 34) was appointed Speaker of the House of Commons.