Years before, there had been two or three wars between the kings of Mysore and the kings of Keladi. In these wars, the rulers of 
Mysore had been defeated. As the kings of Keladi had a long seacoast under them, they reaped considerable profits from the 
foreign traders, the Dutch and the English.

At the time Chennamma was ruling in Keladi, the ruler in Mysore was Chikkadevaraya Wodeyar. A person by name Andhaka Venkata Nayaka also belonged to the dynasty of Keladi kings. He wrote a letter to the Mysore ruler; he said, "I should have been the King of Keladi. But Chennamma came in the way. Therefore if you will fight with her and help me to get the kingdom, I shall give half of it to you and render other help also."

Chikkadevaraya was very pleased with the letter. He thought it would be quite easy to win the kingdom which was in the hands of 
a woman. If he did so, all the foreign trade now under Keladi would be in his hands. So he began preparations for a war.

Queen Chennamma was not at all afraid that the Mysore ruler had declared war on Keladi. She remained undaunted and sent a big army under her Commander Bhadrappa Nayaka to fight the enemy. The chieftains of Sode, Sirsi and Banavasi also declared war on Keladi. But the Queen very cleverly managed to defeat them all.

The Mysore army was the first to be defeated. But the next year that army defeated the Keladi force. Again when there was a war, the Queen was victorious. Several officers of the Mysore army were captured. But the Queen treated them with courtesy. She also set them free. Because of this, Chikkadevaraya developed a high regard for the Queen. The rulers of Mysore and Keladi signed a treaty of friendship.

Queen Chennamma had banished some leaders who had their eyes on the throne. Now all those men, obtaining the help of other rulers, began a war with the Queen. But the able Queen defeated them.

Chennamma had adopted Basappa Nayaka. He was to become the King later. So she gave personal attention to his training and education. Every morning after her bath, prayers and breakfast, she would go to the court hall. She would stay there till mid-day, and listen patiently to any of her subjects who had any difficulties. She would give them whatever help was necessary. She would discuss matters of statecraft and administration with Basappa Nayaka and her ministers and officers and give her decisions. After the midday prayers and worship, she would spend an hour giving alms. At that time monks, sanyasis, priests and the poor and the needy would all receive help.