Hi Colin,
I have followed the William from 1881 census. If he is your one he appears to have married 2 Elizabeth/Elizas.
On 1881 Census he has a much younger wife than the 1841 Census
1851 Census
Rodborough, Glous
HO107/1965/470/5
William POOLE, Head, Widower, 37, Master Shoemaker, born Glous, Rodborough
Fanny, 5, Daug
Morris, 3, Son
George, 1, Son, all born Rodborough
Jane Ridley, Servant, 13
1861 Census he is still a widower, 3 children still at home in Rodborough. RG9/1776/84/10
He is now born Bath, Somerset
1871 Census
Rodborough, Glous
RG10/2637/8/7
William POOLE, Head, Mar, 56, Shoemaker, born Batts(sic), Somerset
Eliza, Wife, Mar, 40, Woollen Cloth Worker, born Bisley, Glous
George, Son, Unm, 22, Carpenter/journeyman, born Rodb, Glous
Lydia, Daug, 3, born Rodb
Alice, Daug, 1 , born Rodb
So remarried about 1866ish
Possible Marriage ( there are others but this seem to fit);
William POOLE
Eliza MAY ( on same page)
June 1867
Stroud 6a 531
1881 he is born Bath, aged 66 as you say and Elizabeth 50 born Bisley. Alice is still at home and new child Henry aged 8.
If this is all correct first Eliza died abt 1850 after birth of George.
So just before 1851 census.
A birth cert of one of the younger children eg Alice, would confirm details of Eliza and whether William was a widower.
Marriage cert of William to either Eliza/Elizabeth would give his Fathers name.
Cheers,
Trish