To give weight to this declaration, he appeared with his whole force before Berlin. "I will not be worse treated than the imperial generals," was his reply to the ambassadors whom the bewildered Elector despatched to his camp. "Your master has received them into his territories, furnished them with all necessary supplies, ceded to them every place which they required, and yet, by all these concessions, he could not prevail upon them to treat his subjects with common humanity. All that I require of him is security, a moderate sum of money, and provisions for my troops; in return, I promise to protect his country, and to keep the war at a distance from him. On these points, however, I must insist; and my brother, the Elector, must instantly determine to have me as a friend, or to see his capital plundered." This decisive tone produced a due impression; and the cannon pointed against the town put an end to the doubts of George William. In a few days, a treaty was signed, by which the Elector engaged to furnish a monthly subsidy of 30,000 dollars, to leave Spandau in the king's hands, and to open Custrin at all times to the Swedish troops. This now open alliance of the Elector of Brandenburg with the Swedes, excited no less displeasure at Vienna, than did formerly the similar procedure of the Duke of Pomerania; but the changed fortune which now attended his arms, obliged the Emperor to confine his resentment to words. The king's satisfaction, on this favourable event, was increased by the agreeable intelligence that Griefswald, the only fortress which the Imperialists still held in Pomerania, had surrendered, and that the whole country was now free of the enemy. He appeared once more in this duchy, and was gratified at the sight of the general joy which he had caused to the people. A year had elapsed since Gustavus first entered Germany, and this event was now celebrated by all Pomerania as a national festival. Shortly before, the Czar of Moscow had sent ambassadors to congratulate him, to renew his alliance, and even to offer him troops. He had great reason to rejoice at the friendly disposition of Russia, as it was indispensable to his interests that Sweden itself should remain undisturbed by any dangerous neighbour during the war in which he himself was engaged. Soon after, his queen, Maria Eleonora, landed in Pomerania, with a reinforcement of 8000 Swedes; and the arrival of 6000 English, under the Marquis of Hamilton, requires more particular notice because this is all that history mentions of the English during the Thirty Years' War.