Here's the entry from the 1915 editon of "Ayres' Lawn Tennis Almanack" on Robert B. Powell, probably the most successful Canadian lawn tennis player before World War One:
"Powell, Robert Branks. B
. Victoria, British Columbia, April 2, 1881. (Private Secretary to Sir H. Joly de Lotbiniere, K.C.M.G., Lieutenant-Governor of British Columbia, 1900-1904; in charge of arrangements in connection with the visit of Prince and Princess of Wales to B.C., 1901, when he was attached to staff of Lord Minto, Governor-General of Canada; appointed to Government Service in Fiji, 1904; employed on Governor's Staff and on Western Pacific High Commission, 1905-1906; passed final examination for the English Bar, May 1909; Fellow of Royal Colonial Institute.)
"Learnt lawn tennis on father's courts at Victoria; was four times champion of British Columbia; won Champ. of Pacific N.W. States of America, 1901; Champ. of State of Oregon, 1904; founded North Pacific L.T.A. (embracing Western States of America and British Columbia clubs), and won Association's first Internat. Champ. at Victoria, 1904; Singles Champs. of Fiji, 1905-6; in semi-final All-Comers' Singles at Wimbledon, won Champ. of Scotland (singles and doubles), singles at Vienna (defeating M. Decugis), represented Canada in Olympic Games at Wimbledon, 1908; won Northern Champ. at Manchester, All England Plate at Wimbledon, Sussex Champ. at Brighton, Doubles at Eastbourne (with K. Powell), at Queen's Covered Courts (with M.J.G. Ritchie), and at Cannes (with F.G. Lowe), and in semi-final of Champ. Doubles at Wimbledon (with K. Powell), 1909; won Scottish Champ. and in final of Champ. Doubles (with K. Powell) and of mixed doubles with (with Mrs Sterry) at Wimbledon 1910; won Dawlish singles cup outright, 1913; member of English (Drive Club) team in South Africa, 1910-11; won mixed doubles at Dinard, singles at Dawlish, and represented London v. Paris at Auteuil, 1911; won doubles (with F.L. Riseley) at and mixed at Dinard and represented All England Club v. Germany at Wimbledon, 1912; captain of Canada v. South Africa at Queen's, v. Belgium at Folkestone, and v. America at Wimbledon (final round) in Davis Cup competition in 1913; represented Canada v. Australasia at Chicago, 1914.
"Is a keen horseman and has won amateur races on the flat in Canada and Fiji. Address: Victoria, B.C."
When World War One broke out, Robert B. Powell enlisted in the Canadian infantry and served with the 48th Canadian Infantry Battalion. He saw a lot of action at the front in France, eventually rising to the rank of lieutenant. He was killed in action on April 28, 19197, during the Battle of Vimy Ridge. He was 36.
The wikipedia entry on Robert B. Powell has some good links, here: http://en.wikipedia.org/wiki/Robert_Powell_%28tennis%29
The above entry also features a photograph of the 1913 Canadian Davis Cup team of Powell, Bernard Schwengers, Henry G. Mayes and James F. Foulkes.
A number of Robert B. Powell's singles results, including his complete Wimbledon singles record, can be found here: http://www.tennisarchives.com/coureurs.php