Which country's interests sponsored Martin Frobisher's sailing expedition into the waters of northern Canada?

United kingdom of Great Britain

Explanation:

Martin Frobisher was an English seaman. He is also an English privateer who made three voyages to North America.

In 1574, Frobisher petitioned the Privy Council in Britain for permission and financial support to lead an expedition to find a north-west passage to "the Southern Sea" which is also called the Pacific Ocean.

The second voyage was also sponsor by the British, when Queen Elizabeth lent the 200-ton Royal Navy ship Ayde to the Company of Cathay in 1577.

On 3 June 1578, the third voyages begans which was also sponsor by Britain

Martin Frobisher was the leader of the expedition for the three voyages. The Cathay company was also a great influence in his success on the three voyages.

England

Explanation:

Martin Frobisher's sailing expedition into the waters of northern Canada was sponsored by Queen Elizabeth 1 of England. The Queen believed strongly that there was fertility in the new territory of Canada so she sent Martin Frobisher on a large expedition with about 15 vessels to establish a 100-man colony. This was Martin Frobisher's third trip or voyage to Canada and so he set sail on the 3rd of June, 1578.

He arrived at Frobisher's Bay in Canada July but could not establish a colony which Queen Elizabeth 1 asked him to due to the lack of contentment of his men so instead he he began to mine ore believing to be worth a lot. He mined about 1,350 tons of ore and took back to England. It was in England that it was discovered that the tons of ore was useless and worth nothing.

As a result of this, Martin Frobisher lost a lot of money and was financially incapacitated which made him to look for other means of employment and survival.