Source: Michael Doyle Their Name Liveth For Evermore: The Great War Roll of Honour for Leicestershire and Rutland.
He was the son of Richard Allen a Cement Works Labourer, born 1862 in Sileby, Leicestershire and his wife Jane, born 1863 in Cossington, Leicestershire. Harry was a Brickyard Labourer and was born in 1896 in Sileby, Leicestershire, his siblings were John Edward, born 1894 in Cossington, Leicestershire, Arthur, born 1901 in Sileby, Leicestershire and Joseph Albert, born 1905 in Sileby, Leicestershire, in 1911 the family home was at Barrow Road, Sileby, Leicestershire. The War Diary for today records that the Battalion were in the Front Line left subsection Dickebusch sector. Quiet day in Battalion sector. Commanding Officer at conference at Brigade HQ’s where he learnt that an enemy attack was expected on the 22nd instant. Following dispositions assumed during the night of the 21st/22nd instant in view of this attack. Battalion HQ’s moved to new HQ’s at H.32.b. 50.60 (permanent change). B and D Company’s moved to battle positions in Vyverbeek Line. 1 platoon from each of A and C Company’s withdrawn from front line Evyverbeek Line. Counter preparation by artillery indulged in fully during the night and evoked fairly heavy retaliation, chiefly on Vyverbeek Valley. Except for this retaliation enemy behaved normally and as at 2.30am there were no signs of the expected attack. Company’s resumed normal dispositions. Casualties A Company 8 killed, 3 wounded, 1 missing. B Company 3 wounded, 1 missing. D Company 1 killed.

Source: Leicestershire War Memorials Project.
Photograph kindly supplied by T. Allen, great nephew, in 2014