Not sure what you would include as ancient leader, but AL Maqrizi was a Mamluk administrator/intellectual in Egypt in the 15th century who wrote a magnificent work on the economic troubles of Egypt 808 Hijri (1405 AD). He deals with concepts like inflation, which he termed as "ghala'", over-printing of money, effective governance and other concepts. Basically we would consider it as a work on monetary policy today. He also discusses the causes of food shortages and the government policy appropriate for preventing it and why food shortages happen. There is a sort of Keynesianism to his conclusions about counter-cyclical spending in relation to famines, and natural vs artificial famines that is present in the work of Amartya Sen and Mike Davis.

He Mostly blames the Circassian Mamluke administration for the decline in Egypt due to 3 main policies: currency devaluations due to cessation of silver coins and use of copper without stable exchange rate; venality in offices and bribery to get positions (Initially way to get quick money, make people in position pay for it, became outright buying of position including judges and religious positions); heavy taxation of peasants by fief holders. His solution is to base currency on silver and gold only.

Today scholars say he got some things right and other things wrong. Of the things he overlooked: He perhaps could not have known that the scarcity of silver in Egypt was due to the high demand for silver in Europe. The Venetians, the main trading partner for Egypt, therefore stopped selling them silver which came from central Asia and Iberia. Egypt's trade balance due to a stagnation of industry during this time also meant they had nothing to trade for the silver or the gold from West Africa. Another factor was that Egypt just came out of a series of plagues, (black death) that also hit it pretty heavily. Third it was not uncommon for rulers to devalue currency to pay back debts at the time, even in Europe. Finally, AL-Maqrizi was a Shafi'i Muslim who believed that the prophet favored silver and gold currency over copper (which we know is inaccurate today as he did issue copper currency). His belief that these metals would have a stable value over time due to them having some inherent value is today discredited as unrealistic, though some people still talk about bringing back the gold standard.

Main Source: Mamluk Economics by Adel Allouche, 1994