The Treasury is the government’s economic and finance ministry, maintaining control over public spending, setting the direction of the UK’s economic policy and working to achieve strong and sustainable economic growth.

Ministers

A Treasury is either:

 Originally, a place where money, gold and other treasure is kept.
 Today, a government department which deals with money supply, taxation and financial policy.

History

The treasury as a place to keep the king's (or city's) gold and valuables has a long history. The winners in a war would take back whatever they wanted, and slaves and booty were top of the list. The first recorded booty in history is a stele taken during 1160 BC.

The earliest found artefacts made of silver and gold are from Lake Varna in Bulgaria dated 4250–4000 BC, the earliest made of copper are dated 9000–7000 BC.

"...And there was also silver weighing many thousands of talents and all the royal treasure amounting to a very great sum..." Procopius of Caesarea.

The term treasury was first used in classical antiquity to describe the places built for gifts to the gods. An example is the Siphnian Treasury in Delphi. Many similar buildings were put up in Olympia, Greece by city-states hoping to impress others during the ancient Olympic Games. In Ancient Greece treasuries were almost always inside religious buildings such as temples. This made state funds sacrosanct, and adding moral constraints to the punishment for thieves.

The sovereigns' treasury in the palace in ancient Jerusalem,was similar in nature to the temple treasury. Those treasuries had officials, and worked rather like a bank.

"...in fact, practically in every city there are banking places for the holy money..." Philo.

In excavations of Persopolis a text about to the activities of a treasury were discovered. It dates to the fifth century BC. The texts were written in the Elamite language.

The ancient Roman word aerarium signified the treasury of the Senate, fiscus was used to indicate the imperial treasury used by Caesar.
 They had, as we do, the distinction between a treasury as a store of valuables, and the treasury as an office of finance.

Treasuries in modern government

H.M. Treasury 
In the United Kingdom, Her Majesty's Treasury is overseen by the Chancellor of the Exchequer.  The traditional honorary title of First Lord of the Treasury is held by the Prime Minister. Her Majesty's Revenue and Customs administers the taxation system.

In the United States, the Treasurer reports to an executive-appointed Secretary of the Treasury. The IRS is the revenue agency of the US Department of the Treasury.

Ministry of Finance 
In many other countries, the treasury is called the Ministry of Finance. Its head is known as the Finance Minister. Examples include New Zealand, Canada, Malaysia, Singapore, Bangladesh, India, Pakistan,  and Japan.

Both 
In some other countries, a Treasury will co-exist with a separate Ministry of Finance, with divided functions.

The government of Poland includes the Ministry of Finance as well as the Ministry of State Treasury, as does the government of the Ukraine. It was the same in Italy before the creation of the united Ministry of Economy. In the Australian federal government a treasurer and a finance minister co-exist.

References 

Finance
Government