With bit of reading between the lines and added punctuation, I get the following:

Le lieu de retraicte est Ay, desquels [,] oultre les rançons particulières des habitans, [--] qui deux, qui trois pistolles ou plus,[--] [ils (l'armée) leur] ont exigé [,] pour en sortir [,] onze mil livres... Cette brigade tient tous les vilages des environs en crainte, et personne ne s'expose aux champz ou il est volé

This gives something like:
The place they (the people of the area) retreated (in)to was Ay, to escape from where, apart from/in addition to individual "ransoming" (i.e. extortion) of the inhabitants [by soldiers] -- some (of the soldiers) being armed with two pistols, some with three or more -- they had to pay the £11,000 (collectively?) demanded (by the soldiers/army) … This brigade/gang of brigands (?) held all the surrounding villages in the grip of fear, and no one ventured out into the fields, or he was robbed

NB: brigade, from Latin brigata = troupe, from briga = lutte [military unit]
brigand, from Latin brigante = qui va en troupe [brigand, ruffian]

So:
The people found refuge in Ay. However, to escape from there they had to pay the £11,000 demanded by the soldiers, in addition to individual extortion by brigands armed with two, three, sometimes more pistols ... This gang of brigands held all the surrounding villages in the grip of fear, and no one ventured out into the fields, for fear of being robbed



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Note added at 3 hrs 45 mins (2005-02-05 22:23:10 GMT)
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I think you\'ve realized by now, Mark, that Old French sentence structure - indeed, the logical thought processes of the time? - was not as reliable as it is expected to be these days, possibly/probably because anything written was intended necessarily for a select few who, chances are, already had a good picture of events. Exceptions being written versions of orally presented stories, but here too, the audience already knew the story as a rule, so non sequiturs went unnoticed. (possibly in 500 years times someone will say the same about our cinema - there\'s a (at least one) site on the Internet that points out bloopers in films, be it visible camera crew in crowd scenes, L/R inversions, continuity errors (non sequiturs) ... Plus ça change, plus ça reste la même chose ...)

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Note added at 7 hrs 12 mins (2005-02-06 01:50:24 GMT)
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WRONG WRONG WRONG

I stand corrected. Your reference to Spain has made me realize that the \"pistolles\" are not weapons but a unit of currency, the Spanish (originally) gold pistole (note spelling, with a final E; English spelling, not French).

pistole - A name formerly applied to certain foreign gold coins ...; spec. from 1600 applied to a Spanish gold coin worth 16s. 6d to 18s.
[SOED]
Worth 16 shillings and sixpence to 18 shillings (there being 20 shillings in an English pound).

For Larousse Lexis, \"1. Monnaie d\'or ancienne frappée d\'abord en Espagne. 2. Monnaie de compte exprimant une valeur fixe de 10 livres\"