Am I right in thinking it is dated Feast of the Purification of the blessed Mary in the 33rd year of Edward son of Henry
Yes.
Just to save time, and as there is no palaeography involved, I put your text through
https://www.perplexity.ai/ with the following result:
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This medieval Latin text appears to be a legal agreement between Henry, the Abbot of Cirencester, and John de Latton and his wife Isabella. Here's an English translation of the document:
To all the faithful of Christ who will see or hear the present writing, Henry, by Divine permission Abbot of Cirencester, and the Convent of the same place, send greetings in the Lord. Let it be known to all of you that we have granted to John de Latton and Isabella his wife, in the form and condition written below, namely:
Each week, as long as they shall live together, fourteen white coronarii (a type of coin) and nine gallons of beer, that is, five gallons of conventual beer and four of chaplains' beer, and one dish each day from our kitchen, just as free servants receive daily from our house. If the said Isabella should outlive him, immediately after the death of the said John, half of all the above grants shall entirely cease.
And for this grant, the aforesaid John has totally remitted to us and our Church, and quitclaimed for himself and his heirs in perpetuity, all right and claim which he had or could have in any way, with any reversion, in the lands and tenements with all their appurtenances which Walter, father of the aforesaid John, held of us in Latton. And the said John and his heirs shall fully and completely warrant the said lands and tenements to us and our Church without any diminution.
And if it should happen (which God forbid) that the aforesaid John and Isabella should fail in any way in the aforesaid warranty, or claim or vindicate any right or claim in the said tenements, then the said Abbot and Convent shall entirely cease from all provision of the premises without challenge from anyone forever.
In witness whereof, the aforesaid parties have alternately affixed their seals to this indented writing. Given at Cirencester on the Feast of the Purification of the Blessed Mary, in the thirty-third year of the reign of King Edward, son of Henry.
Key PointsGrant: The Abbey provides John and Isabella with weekly allowances of money, beer, and food.
Condition: The grant is reduced by half if Isabella outlives John.
Exchange: John relinquishes all claims to lands and tenements in Latton.
Warranty: John and his heirs must guarantee the lands to the Abbey.
Clause: If John or Isabella breach the agreement, the Abbey can cease all provisions.
This document, dated to the 33rd year of Edward I's reign (1305), exemplifies the complex land and support arrangements common in medieval England between religious institutions and local gentry.
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In general, this looks pretty good, but I'll run through it in more detail if I have time later.