The town of Étampes, which, until recent decades (when the R.E.R. line from central Paris was completed, transforming it into a bedroom suburb of Paris) was something of a backwater, enjoyed an extraordinary essor during a short period, early in the history of the Capetian dynasty (between the early 11th and later 12th centuries). Although it remained an important fief of the Crown in subsequent centuries, the town never really regained its prominence, which was based upon its supreme strategic position in these years.
  Although the pagus stampensis is mentioned in Gregory of Tours, the town itself (as a "castrum") only first appears in the sources in 1030, when King Robert the Pious issued a charter from the "palace of Étampes,"(1) which "palace" in this castrum Queen Constance had built (according to Helgaud of Fleury, the biographer/hagiographer of King Robert the Pious), at which point this "palace" then became something of a favorite hangout of the king.(2)
  In any event, Helgaud of Fleury tells us that King Robert was responsible for the foundation (among other churches throughout the realm) of the "monastery of St. Mary in the castrum of Étampes,(3) and also, in the same castrum, of a church in the palace...."(4)
  By the early 12th century there was a very substantial royal "castle" built on the hill overlooking the town, later known as the "Tour Guinette."(5)  Before its near-complete destruction in the early modern and revolutionary periods, this fortified tower (and its no doubt substantial ancilliary complex of buildings) would have given the town a destinctive "Regnum/Sacerdotum" topographic profile, not unlike that which could be seen in a great many contemporary towns and cities of the realm (such as Epernon, Provins, and Chartres, which once had a massive comital "castle" sharing the top of its hill-like scarp with the towers of the cathedral).
  This stronghold was certainly a significant, necessary and very visible representation of the stratigic significance of the town for the Capetian kings ; the present structure might well have been preceded by a somewhat less substantial (though still serviceable) one in wood or stone built in the time of King Philip I, who is said, in the account of the Miraculi Sancti Benedicti written by a monk of Fleury, to have been "chased all the way to Etampes" by the Lord of LePuiset after his unsucessful first siege of that notorious castrum in the Beauce.(6)
  In any event, from the remains we have left it seems clear that his son, Louis VI, considered the site important enough to warrant a significant investment of resources, perhaps during the crucial period of his struggles with the nearby castelains of Montlhery, Corbeil, etc.
  By the time of Philip Augustus the importance of Etampes and its tower as a royal stronghold had not really decreased, although, given the changed geopolitical situation both within and beyond the royal domain, it had been transformed somewhat : it was at Etampes that the king chose to imprison his erstwhile wife, Ingeborg of Denmark, to keep her safe from rescue by her kinsmen, for no less than a decade, after whatever it was which passed between them on their wedding night.

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Notes :

  (1) Robert's charter does not concern the castrum of Étampes itself, but was done at the request of Abbot Adraud of St.-Germain-des-Près, and survives in numerous copies and as a sealed original, Arch. nat., K 18 no. 6.  For these see William Mendel Newman, Catalogue des Actes de Robert II, Roi de France (Paris, 1937), no. 84, p. 104, with a discussion of the problem related to the date in note 1 (both Pfister and Poupardin had earlier dated it to 1031, before 31 March).
   Mabillon published a facsimile of part of this charter (De re diplomatica, p. 421, no 2, tabletta 38) and the whole text was published in the RHGF, X, p. 623, no. 51.

   (2) Robert-Henri Bautier, ed., Helgaud de Fleury, Vie de Robert le Pieux, Epitoma Vitae Regis Rotberti Pii. (Paris: CNRS, 1965), p. 64 : "Stampis castro, regina Constantia palatium construxerat nobile simul cum oratario; quo delectatus rex ad prandendum cum suis l[a]ectus assedi.." Bautier notes (p.64, note 1, citing M. Prou, "Une ville-marché au XIIe sièecle, Étampes", Mélanges d'histoire offerts à H. Pirenne, p. 4) that this "palatio" was located "between the rue de la Juiverie and those of la Roche-Plate and la Vigne," ; that it was destroyed during the reign of Henry IV ; and that Queen Constance, daughter of Count William of Provence and Alix of Anjou, married Robert between 1001 and 1003 and died at Melun in July, 1032. This "oratorio" was, apparently, the parish church of St. Basile (see below, note 4).

  (3) Ibid., p. 130 : "Fecit...monasterium sanctae Mariae, in Stampensi castro; item in ipso castor, aecclesiam unam in palatio..." Note 9 : "The donations made by Robert to the canons of Notre-Dame of Étampes are known by a 1046 act of King Henry I (Soehnée, no. 73, p. 76 and, following him, Newman, no. 99, p. 124). If we can believe the canons, the church was built in 1022 (arrêt du parlement, 23 January, 1572, cited by J.-M. Alliot, ed., Cartulaire de Notre-Dame d'Étampes, 1888, p. 145).
  "From the original church of King Robert only the crypt remains, which seems to have been built to recieve the relics brought from Rome by the King in 1016 (see L.-E. Lefévre in the Annales de la Société historique et archéologique du Gâtinais, XXV, 1907, p. 152, and J. Hubert, L'art préroman, 1938, p. 75.)

  (4) "Fecit [rex]...monasterium sanctae Mariae, in Stampensi castro; item in ipso castro, aecclesiam unam in palatio..."  (Bautier, Ibid., p. 131, with this interpretation at p. 131, n. 10 : "This church would be the present parish church of St. Basil, which first appears by name in the confirmation charter of 1046 by Henry I [Alliot, Ibid., p. xv].")
   But the question arises, how could St. Basil's be the "aecclesiam...in palatio" ? What was this "palatio" ?  And why couldn't the "acclesia in palatio" have been a palace chapel?  Surely, we would prefer the text to have read either "capella in palatio" or "ecclesiam in castro", either of which would be less ambiguous than what we have been given.  But, that's the nature of "History".
   It would seem, from the reference to the "monasterium sanctae Mariae in...castro", that the "castrum" was, in King Robert's time, the "lower" town, not the hill upon which the later Tour Guinette was built ; so the identification of St. Basile with this church would seem to be, at least, possible. But, if we accept this reading, then the "palatio" of the Queen was a bit up the hill from St. Mary's and encompassed an area which included that around the present church of St. Basile.
(5) [Insert bibliography and discussion of the Tour Guinnette]

(6) [Miraculi Sancti Beneditci citation.]

(7)