According to Will Pasto in Quora (an online newsletter), "During the Palestinian Campaign of WWI (1917), the British were in their trenches and the Ottomans were in theirs, but there was little movement. The British learned that the opposing Turks had run out of cigarettes, so the intelligence service of the British Army came up with the idea of throwing cigarettes to the Turks, but they would wrap the packs in paper with slogans encouraging the Ottomans to stop fighting.
"This didn't work; the Turks would throw the slogans away and enjoy the cigarettes. Shortly before a raid was scheduled, the British changed tactics a bit. The cigarettes they threw over the top still had slogans on them, but they also had the added benefit of being heavily laced with heroin. By the time the raid started, the British met essentially no opposition."