Editing Empress Matilda (section)

===Initial moves===
[[File:Political map of England 1140.PNG|thumb|alt=A colour coded map of England showing the political factions in 1140|Political map of Wales and southern England in 1140; areas under Matilda's control (blue); Stephen's (red); Welsh (grey)]]
Empress Matilda's invasion finally began at the end of the summer of 1139. Baldwin de Redvers crossed over from Normandy to [[Wareham, Dorset|Wareham]] in August in an initial attempt to capture a port to receive Matilda's invading army, but Stephen's forces forced him to retreat into the south-west.<ref name=DavisP39>{{harvnb|Davis|1977|p=39}}</ref> The following month, the Empress was invited by her stepmother, Queen Adeliza, to land at [[Arundel]] instead, and on 30 September Robert and Matilda arrived in England with a force of 140 knights.<ref name=DavisP39/>{{refn|Edmund King disagrees that the Empress received an invitation to [[Arundel Castle|Arundel]], arguing that she appeared unexpectedly.<ref>{{Harvnb|King|2010|p=116}}</ref>|group="nb"}} Matilda stayed at [[Arundel Castle]], while Robert marched north-west to [[Wallingford, Oxfordshire|Wallingford]] and Bristol, hoping to raise support for the rebellion and to link up with [[Miles of Gloucester]], who took the opportunity to renounce his fealty to the King and declare for Matilda.<ref>{{harvnb|Davis|1977|p=40}}</ref>

Stephen responded by promptly moving south, besieging Arundel and trapping Matilda inside the castle.<ref name=BradburyP78>{{harvnb|Bradbury|2009|p=78}}</ref> Stephen then agreed to a truce proposed by his brother Henry; the full details of the agreement are not known, but the results were that Matilda and her household of knights were released from the siege and escorted to the south-west of England, where they were reunited with Robert of Gloucester.<ref name=BradburyP78/> The reasons for Matilda's release remain unclear. Stephen may have thought it was in his own best interests to release the Empress and concentrate instead on attacking Robert, seeing Robert, rather than Matilda, as his main opponent at this point in the conflict.<ref name=BradburyP78/> Arundel Castle was also considered almost impregnable, and Stephen may have been worried that he risked tying down his army in the south whilst Robert roamed freely in the west.<ref>{{harvnb|Bradbury|2009|p=79}}</ref> Another theory is that Stephen released Matilda out of a sense of [[chivalry]]; Stephen had a generous, courteous personality and women were not normally expected to be targeted in Anglo-Norman warfare.<ref>{{harvnb|Gillingham|1994|p=31}}</ref>{{refn|"[[Chivalry]]" was firmly established as a principle in Anglo-Norman warfare by the time of Stephen; it was not considered appropriate or normal to execute elite prisoners and, as historian John Gillingham observes, neither Stephen nor Matilda did so except where the opponent had already breached the norms of military conduct.<ref>{{harvnb|Gillingham|1994|pp=49–50}}</ref>|group="nb"}}

After staying for a period in Robert's stronghold of Bristol, Matilda established her court in nearby Gloucester, still safely in the south-west but far enough away for her to remain independent of her half-brother.<ref>{{Harvnb|Chibnall|1991|pp=83–84}}; {{harvnb|White|2000|p=36}}</ref> Although there had been only a few new defections to her cause, Matilda still controlled a compact block of territory stretching out from Gloucester and Bristol south into [[Wiltshire]], west into the Welsh Marches and east through the [[Thames Valley]] as far as Oxford and Wallingford, threatening London.<ref>{{harvnb|Bradbury|2009|p=81}}; {{harvnb|White|2000|pp=36–37}}</ref> Her influence extended down into Devon and Cornwall, and north through [[Herefordshire]], but her authority in these areas remained limited.<ref>{{harvnb|White|2000|p=37}}</ref>

Matilda faced a counterattack from Stephen, who started by attacking [[Wallingford Castle]] which controlled the Thames corridor; it was held by Brian Fitz Count and Stephen found it too well defended.<ref>{{harvnb|Bradbury|2009|pp=82–83}}; {{harvnb|Davis|1977|p=47}}</ref> Stephen continued into Wiltshire to attack [[Trowbridge#Castle|Trowbridge]], taking the castles of [[List of castles in Gloucestershire|South Cerney]] and [[Malmesbury]] en route.<ref>{{harvnb|Bradbury|2009|pp=82–83}}</ref> In response, Miles marched east, attacking Stephen's rearguard forces at Wallingford and threatening an advance on London.<ref>{{harvnb|Davis|1977|p=42}}</ref> Stephen was forced to give up his western campaign, returning east to stabilise the situation and protect his capital.<ref name=DavisP43>{{harvnb|Davis|1977|p=43}}</ref>

At the start of 1140, Bishop [[Nigel of Ely]] joined Matilda's faction.<ref name=DavisP43/> Hoping to seize [[East Anglia]], he established his base of operations in the [[Isle of Ely]], then surrounded by protective [[fen]]land.<ref name=DavisP43/> Nigel faced a rapid response from Stephen, who made a surprise attack on the isle, forcing Nigel to flee to Gloucester.<ref name=BradburyP88>{{harvnb|Bradbury|2009|p=88}}</ref> Robert's men retook some of the territory that Stephen had taken in his 1139 campaign.<ref name=Bradbury2009P90>{{harvnb|Bradbury|2009|p=90}}</ref> In an effort to negotiate a truce, Bishop Henry held a peace conference at Bath, at which Matilda was represented by Robert.<ref>{{Harvnb|Chibnall|1991|p=92}}</ref> The conference collapsed after Henry and the clergy insisted that they should set the terms of any peace deal, which Stephen's representatives found unacceptable.<ref name=Bradbury2009P90/>