be given to Montgomery when he arrived and for a three-day conference at Montgomery's headquarters at St Paul's School, London where the plan and alternatives were discussed with the COSSAC, air and naval staffs. Eisenhower arrived in the UK on 15 January and another conference was held at his headquarters at Norfolk House on 21 January, where Montgomery's plan was tentatively accepted. Montgomery's rejection of the Overlord plan did not sit well with the COSSAC staff, who now formed part of Eisenhower's Supreme Headquarters Allied Expeditionary Force (SHAEF). Montgomery once wrote to the CIGS, General Sir Alan Brooke about de Guingand, "I do not know what I should do without him as he is quite 1st class". De Guingand was indispensable to Montgomery, not only in battle but also in relations with the Americans. Montgomery was unpopular with them. In part this was due to American nationalism, but this was only a contributing factor. Montgomery's abrasive personality, his arrogance, condescension and frequent tactlessness, often worked against him and the British cause. Recognising his own limitations and de Guingand's diplomatic skill, Montgomery would often send de Guingand to meetings in his place, but this practice could also cause resentment. In de Guingand Montgomery had a diplomatic but forceful advocate on controversial issues. De Guingand formed a close relationship with Bedell Smith, now Eisenhower's chief of staff at SHAEF and was able to smooth over many difficulties arising from Montgomery's poor relationships with many of his peers and superiors. De Guingand was highly respected by the Americans, General of the Army Omar Bradley, who served under Montgomery's command as the commander of the First United States Army and US 12th Army Group, described de Guingand as Headquarters organisation In the lead up to Operation Overlord, Montgomery left dealing with the details up to de Guingand and the staff, while he spent most of his time touring the country and talking to the troops. In his absence, de Guingand was in charge at St Paul's. He chaired the daily staff conferences and attended inter-staff meetings with his opposite numbers from the Royal Navy and RAF, Rear Admiral George Creasy and Air Vice Marshal Philip Wigglesworth. Montgomery noticed that de Guingand was showing signs of stress and fatigue and instructed Lieutenant-Colonel Harry Llewellyn to report to him if de Guingand was unable to carry out his duties. For the first time Montgomery's command included