123rd Battalion ( Royal Grenadiers ) , CEF The 123rd ( Royal Grenadiers ) Battalion , CEF was authorized on December 22 , 1915 . They were based in Toronto , Ontario , and began recruiting right away , although some members had signed up for service as early as September 1915 . The Battalion recruited , trained and mobilized as an infantry battalion in the Canadian Expeditionary Force during the First World War . Many senior members of the 123rd Battalion were serving with the 10th Royal Grenadiers prior to attesting in the 123rd Battalion . They had trained at home as infantry soldiers . The 10th Royal Grenadiers also contributed approximately 30 % of the soldiers who attested in the 3rd Battalion ( Toronto Regiment ) , CEF starting in September 1914 . The Battalion was separated into two groups in Halifax for mobilization to England , the first group sailing on the S . S . Cameronian and the second group sailing on the S . S . Metagama , arriving in England August 17 and 18 , 1916 , respectively . They mobilized with the 124th Battalion ( Governor General ' s Body Guard ) , CEF . On January 17 , 1917 , the Battalion was redesignated as the 123rd Pioneer Battalion ( Royal Grenadiers ) , CEF , but continued to report up through the Infantry Division , while most of the other Canadian Pioneer Battalions reported through the Canadian Engineers . They commenced training as Pioneers , under the guidance of a Major of the British Pioneers . Many of the original members were fully trained as infantry solders and as pioneers . The 123rd Battalion was commanded by Lieutenant - Colonel Walter Bernard Kingsmill from the time of attestation , until May 1918 , when the Battalion was broken up to form the 7th and 8th and 9th Battalion , Canadian Engineers . Throughout 1917 and into early 1918 , the 123rd Battalion absorbed large contingents of reinforcements , primarily from the 129th Battalion , 3rd Canadian Pioneer Battalion and 3rd Reserve Battalion , and others . In many cases the 123rd Battalion served with front line troops , and in fact , in front of the front line troops , to improve roads , and establish battlements and fortification for the front - line troops to use and occupy . They suffered many casualties . Often they would build plank roads to facilitate movement of troops , artillery pieces , and supply columns , only to have the Germans shell the roads , requiring immense efforts to get Canadian forces to and from the front . Many brave solders were wounded or died while serving with the 123rd Battalion , and many officers and men were decorated for their courageous acts . The 123rd Battalion was demobilized and disbanded on September 15 , 1920 , at the same time most C . E . F . Battalions were disbanded . The 123rd Battalion is perpetuated by The Royal Regiment of Canada of Canada ' s 32nd Brigade Group , the largest reserve regiment in Canada ' s militia forces today . The Royal Regiment of Canada also perpetuates the 3rd Battalion ( Toronto Regiment ) , CEF , 58th Battalion , CEF , 124th Battalion ( Governor General ' s Body Guard ) , CEF , the 170th Battalion ( Mississauga Horse ) , CEF , and the 204th Battalion ( Beavers ) , CEF . References . Meek , John F . Over the Top ! The Canadian Infantry in the First World War . Orangeville , Ont . : The Author , 1971 . War Diaries of the 123rd Battalion : February – August 1917 . Library and Archives Canada War Diaries of the 123rd Battalion : September – November 1917 . Library and Archives Canada War Diaries of the 123rd Battalion : December 1917 - May 1918 . Library and Archives Canada Battle Royal : Lieutenant - Colonel Donald James Goodspeed , CD , Canadian Military Historian ; Published by Royal Regiment of Canada Association : Toronto ; MacMillan ; First Ed . 1962 and Second Ed . 1979 .