The Russians were unable to commit a large portion of their troops to the Caucasus region, because Alexander's attention was continually distracted by simultaneous wars with France, the Ottoman Empire, Sweden and Great Britain. Therefore, the Russians were forced to rely on superior technology, training, and strategy in the face of an overwhelming disparity in numbers. Some estimates put the Persian numerical advantage at five to one. Shah Fath Ali's heir, Abbas Mirza, tried to modernize the Persian army, seeking help from French experts through the Franco-Persian alliance, and then from British experts, in order to address the tactical disparity between the forces.