In April 1918, during the latter part of World War I, the Viceroy invited Gandhi to a War Conference in Delhi.[95] Gandhi agreed to actively recruit Indians for the war effort.[96][97] In contrast to the Zulu War of 1906 and the outbreak of World War I in 1914, when he recruited volunteers for the Ambulance Corps, this time Gandhi attempted to recruit combatants. In a June 1918 leaflet entitled "Appeal for Enlistment", Gandhi wrote "To bring about such a state of things we should have the ability to defend ourselves, that is, the ability to bear arms and to use them... If we want to learn the use of arms with the greatest possible despatch, it is our duty to enlist ourselves in the army."[98] He did, however, stipulate in a letter to the Viceroy's private secretary that he "personally will not kill or injure anybody, friend or foe."[99]