1899 May 24. Born Bessbrook, Armagh
1901 census at 1 Charlemont Square, Camlough, Armagh
1911 census at school at Lisnagarvy , Lisburn, Antrim
1918 Mar 27. The undermentioned cadets to be temp. 2nd Lts. Royal Irish Reg. Horace Spencer Pearson.
1919 Sep 27. R. Ir. Regt. Temp. 2nd Lt. H. S. Pearson to be temp. Lt.
1919 Oct 20 . R Irish Reg Temp. Lt. H. S. Pearson relinquishes his commission on completion of service, and retains the rank of Lt.
1920 May 31 Joined RIC as a Barrack Defence Sgt
1920 Dec 30 Shot a man trying to escape - he was still a Barrack Defence Officer at this point
1921 Jan 2. Joined ADRIC with service no 1399. Posted to J Coy
Fined £5 by Coy Commander
1922 Jan 23. Discharged on demobilisation of ADRIC
1923 Jan 8. Leaves UK for New York. He was ex-District Inspector in the RIC living at Alma Rd, Monkstown, Dublin. He travels with his mother Madge, and they intend to settle in USA.
1926 Sep 27. The KING has approved the resignation of their commissions by the following officers, with effect, from the dates specified: — IARO .Lieut. H. S. Pearson
1928 Jul 21 Married in New York to Ruth Catherine Gardiner Wheylund Ahneman (1901–1960) (she was divorced)
1940 USA census in New York , married to Ruth. He was a Sales Manager in Real Estate
1942 Draft Card
1960 Aug. Died New York, USA