Short answers, pulled from the story.
Emperor Hirohito approved the offensive on the 24th of January 1944. The Imperial General Staff sought to secure an overland rail route through French Indochina and China for raw materials from south-east Asia.
General Yasuji Okamura took charge of Operation Ichi-Go. The Imperial Japanese Army mobilized 500,000 troops, 100,000 horses, 1,500 pieces of artillery, 800 tanks, 15,000 mechanised vehicles, and 200 bombers.
The goals included securing an overland rail route through French Indochina and China and neutralizing United States Army Air Forces bases near Chengdu, Sichuan. These resources were intended to develop offensives in 1946 while preventing American bombers from attacking the Japanese homeland.
Senshi Sōsho put Chinese losses at 2,432 killed and 858 captured while Japanese losses stood at 50 killed and 149 wounded. Divisional commander Lu Gongliang died when Xuchang fell on the 1st of May.
The Japanese took Changsha on the 18th of June after three days of fighting. The city was defended by three understrength Chinese divisions commanded by General Zhang Deneng.
Overextended supply lines and mounting casualties caused the Japanese to end Operation Ichi-Go before US bases were overrun. The total death toll reached about 100,000 by the end of 1944 due to illness and combat.