Complex sentence: During the Russo-Japanese War of 1904-05 the Russian commanding generals were men of Skobelev's generation but, to Russia's misfortune, they lacked his military genius.
Split into simpler sentences: During the Russo-Japanese War of 1904-05 the Russian commanding generals were men of Skobelev's generation. To Russia's misfortune, however, they lacked his military genius.