Back in Ireland many of Ernie O'Malley's former IRA comrades were now part of the Fianna Fáil government, and the prospect of receiving a military pension from the Irish government convinced O'Malley that a return to Ireland was feasible. Having outstayed his visa in the U.S., O'Malley returned to Ireland in 1935.
On returning to Ireland, Ernie O'Malley immediately headed for Achill Island, where he spent a week along with his old Republican comrade Paedar O'Donnell, his wife Lile and others. O'Malley also issued an invitation for his sweetheart, Helen Hooker, to join him in Ireland. Hooker's father disapproved of O'Malley, but Helen nevertheless travelled to Dublin in 1935. Her mother sent a close family friend, Sarah Sheridan, to report on the suitability of the O'Malley family for marriage into the Hooker family (Helen's sister Blanchette had married John D. Rockerfeller III). Sheridan, formerly the nanny to the Hooker children, was also the grandmother of Catherine Walston, the wife of millionaire British MP Harry Walston and who, allegedly, was later to have an intimate relationship with Ernie O'Malley. Helen and Ernie married in London in September 1935, with Sarah Sheridan in attendance.
In the spring of 1936, Ernie O'Malley's memoirs of the Irish Revolution were published in London by Rich and Cowan under the title 'On Another Man's Wound'. The book had already been rejected by more than a dozen U.S. publishers. Following its publication in London, agreement was reached with U.S. publisher Houghton Mifflin to publish the book in the U.S. under the title 'Army Without Banners'. On Another Man's Wound, the first volume of Ernie O'Malley's memoirs and the only one to be published during his lifetime, has become a classic of revolutionary literature.
The book's publication in Ireland was accompanied by a libel action from a former IRA volunteer and TD, Joseph O'Connor, who claimed that a passage in the book falsely accused him of cowardice in refusing to take part in an IRA raid. O'Connor won the case and the defendants - O'Malley and his Dublin publisher, Sign of the Three Candles, plus the newspaper the Irish Press which had serialised the book - were forced to pay a total of £550 in damages. When bailiffs seized possession of the County Mayo house that O'Malley and Helen were renting, Helen's father offered to pay O'Malley's share of the award. In the end, Ernie O'Malley borrowed £400 to settle his share of the damages.
In the autumn of 1937 Ernie and Helen O'Malley, who had by now given birth to a son, Cahal, rented the Old Head Lodge, Killsallagh, at Louisburgh on the southern shore of Clew Bay, County Mayo. A year later, after searching for a suitable family home, the O'Malleys moved into Burrishoole Lodge. The Lodge, located between Newport and Mulranny on the northern shore of Clew Bay, was an eight bedroom stone house situated across a lagoon from Burrishoole Abbey, the 15th Century Dominican Priory. Ernie O'Malley was particularly pleased that the location had links to the Clan O'Malley and his ancestor Grace O'Malley (Granuille), the notorious 15th Century pirate queen who controlled the waters of the Mayo coast. The Lodge, with its views of Clew Bay and Croagh Patrick in the distance, appealed to Helen and Ernie's artistic instincts, and Helen extended the building to include a studio for her sculpture. After initially renting Burrishoole Lodge, the O'Malleys purchased the buildings and 40 acres of attached land in 1941. The property was extended with the purchase of a further 30 acres of land in 1942.