signatures, the only extant specimens of his handwriting, as proof of his illiteracy, and relates the story that Leslie once told some attendants that his instruction in reading did not reach beyond the letter g (Masson, Life of Milton, ii. 55, footnote).
In early manhood he sought employment as a soldier on the continent. According to Macfarlane he first served under Sir Horatio Vere in the Netherlands, probably as one of the Scottish company which, under the captaincy of Sir Walter Scott, father of the first Earl of Buccleuch, followed Vere from England before 1604. In 1605 Leslie entered the army of the king of Sweden, in which he served with distinction during the next thirty years. He fought under Charles IX of Sweden and under his son, Gustavus Adolphus, in their campaigns against Russia, Poland, and Denmark, as well as against the imperial house of Austria in the thirty years' war.
On 23 Sept. 1626, when Gustavus Adolphus was invested by envoys from Charles I with the order of the Garter at Dirschau, he knighted Leslie, then lieutenant-general, and five others, in the presence of the whole army (Rutliven Correspondence, p. ix). In the same year Leslie signalised himself in an encounter with the Polish troops of Sigismund in the neighbourhood of Danzig.
In 1628, when the Swedish king had flung himself into the thirty years' war, Leslie acted as his chief officer. In May he was sent to take the command at Stralsund, which Wallenstein was besieging. With five thousand Scots and Swedes Leslie fought his way into the town, the stores of which he replenished, and his vigorous action compelled Wallenstein to raise the siege and retire. Leslie was thereupon appointed governor of all the remaining cities along the Baltic coast. Munificent rewards were given him by the citizens of Stralsund, including a medal struck in gold to commemorate the relief of the city (Munro, Expedition, 1637, pp. 75–8). The medal is still preserved by Leslie's descendants.
Leslie continued in command of the Baltic district until 1630, and made it a valuable recruiting-ground for the Swedish armies. The adjacent island of Rugen was meanwhile in the occupation of the imperialist troops, and satisfied that they were incapable of much injury, Leslie for a time ignored their presence. But learning in that year that Duke Bogislaus of Pomerania had privately agreed, with Wallenstein's consent, to cede the island to Denmark, he by a bold sally took possession of it in the name of the king of Sweden (Fletcher, Gustavus Adolphus, 1890, pp. 85, 114, 117).
In recognition of his services Gustavus conferred upon him an estate in Sweden, which was resumed by the Swedish government in 1635 on the ground of some defect in the grant; and if it be true that he received ‘two rich earldoms in Germany’ at the same time, it is clear that the changing fortunes of war soon deprived him of them (State Papers, Dom. 1639, p. 226). A valuable jewel, another gift of Gustavus, with a miniature likeness of the donor, Leslie retained till his death (Fountainhall, Historical Notices of Scottish Affairs, i. 421).
In May 1630 Leslie went to England to advise James, third marquis of Hamilton [q. v.], who had been entrusted by Charles I with the duty of bringing six thousand English soldiers to Gustavus's aid. Leslie acted as sergeant-major-general to Hamilton and his troops. After Hamilton's landing at the mouth of the Oder in Pomerania, Leslie, despite the sickness and death that soon reduced the numbers of the British contingent by a third, captured with their aid the towns of Crossen, Frankfort, and Guben on the Oder. He was afterwards engaged with the British contingent at the recovery of Magdeburg from the imperialists (January 1632), and at the siege of Boxtelude he was in command of the army of Field-marshal Todt, who had fallen into temporary disgrace; but a few days after his arrival a shot from the town struck him on the instep of his left foot while he was viewing the place, and disabled him. He was carried to Hamburg (Swedish Intelligencer, pt. iv. p. 128), but recovered in time to be present at the battle of Lutzen on 6 Nov. 1632, where Gustavus was killed. Subsequently he laid siege to Brandenburg, which surrendered to him on 16 March 1634; and returning to Pomerania, again took part in the reduction of Frankfort on the Oder. Later he was made general of the Swedish armies in Westphalia, where he reduced the castle of Petershagen, took the town of Minden on the Weser, and relieved the garrison of Osnabruck. On the death of Kniphausen in the summer of 1636 he was made field-marshal in his place (Turner, Memoirs, p. 9), and he despatched Colonel Robert Monro [q. v.] to Scotland in order to gain recruits, giving him letters appealing for assistance addressed to Charles I and Hamilton. At the time the position of the Swedish army in Germany was becoming critical. In the latter half of 1637 Leslie was driven from Torgau and down the Elbe to Stettin, whence he crossed to Stockholm in September. The Swedish queen and her chancellor, Oxenstierna, acknowledged the value of his exertions by granting him an annual pension of
