Advowson - is the right in English law of a patron (avowee) to present to the diocesan bishop (or in some cases the ordinary if not the same person) a nominee for appointment to a vacant ecclesiastical benefice or church living, a process known as presentation (jus praesentandi, Latin: "the right of presenting").
The Manor of Water Belchamp alias Belchamp William and Rectory of Belchamp Walter appears on many Manoral Court documents that I have seen.
If you read the WikiPedia pages for Advowson, Lord of the Manor, Demesne, Manor, Messuage, Benefice etc it makes interesting reading with respect to the Manor of Belchamp Walter.
Wikipedia for Advowson
Advowson (/ədˈvaʊzən/) or patronage is the right in English law of a patron (avowee) to present to the diocesan bishop (or in some cases the ordinary if not the same person) a nominee for appointment to a vacant ecclesiastical benefice or church living, a process known as presentation (jus praesentandi, Latin: "the right of presenting").
Found while researching Advowson:
from the information on the The Friends of Holy Innocents Church, Lamarsh website:
The Beauchamps of Bedford Castle were well versed in defence and their North Essex manors were set amongst the many manors of de Vere, with a newly built castle at Castle Hedingham where Matilda, the enemy of Stephen, had been welcomed.
The Normans brought an increased prosperity to the Manors and handed them to wealthy men of their own race who were
able to build churches or chapels adjoining their own demesnes. But it was not until the Normans had been in England for nearly
80 years that the Manor of Lamarsh came into the hands of such a family: the Beauchamps of Bedford.
It was in the reign of King Stephen that this family, loyal to the King, was rewarded by territorial gifts in North Essex when they acquired, amongst others, the manorial lands of Belchamp Walter, Twinstead, Lamarsh and Henny.
When the church was first built the Advowson lay with the Beauchamps but Richard de Beauchamp gave a charter to Colne Priory in which he gave ¼ of a knight’s fee in Alphamstone and Lamarsh, and the Advowson of Lamarsh church, to the monks of Colne, at the instance of his wife Adelina. The document was signed by Payn, Stephen and Walter de Beauchamp.
Rohse deVere was the second husband of Geoffrey de Mandeville, Ist Earl of Essex. The marriage to Payne deBeauchamp meant that the advowson was removed from deVere to Beauchamp. King Steven had a few issues here, with the deVeres, so I don't think that the statement of: "officially held by the deVeres" can be correct.