Originally posted by Silver Dark
Research, in order, Alphabet, Writing, Code of Laws, Literacy, Republic, and switch to it right off the bat from Despotism, while building settlers to expand out across the continent, making new cities and improving the land. Republic then allows enormous gains in scientific and economic advancement, vs. the pace of the same, in Monarchy.
Three problems with the Early Republic strategy:
- Settlers in Republic consume two food, and early on when cities are small this has much greater impact, particularly when you have not irrigated the surrounding terrain yet. In Monarchy settlers consume only one food.
- Every unit except Diplomats and Caravans requires a shield support in Republic. In Monarchy the first three from each city do not require shield support. In small cities this can bankrupt production.
- Citizen unhappiness in Republic cannot be dealt with by adding a defensive unit to impose martial law. Monarchy allows up to three citizens made content by martial law units.
The first two problems compound each other early on, as you are usually producing a settler in a size 2 city, which then drops back to size 1 but has to support a two-food, one-shield settler as it "expands out across the continent". If you have good grassy locations for new cities nearby this will work, until the nearby locations are taken, but if you are traveling anywhere before roads are laid down you will end up with many size 1 cities that cannot grow or produce anything.
Monarchy is the solution to this problem. It is only a stop-gap, as it has significant corruption and a low number of cities before happiness decreases, but it bridges the gap between Despotism and Republic and allows use of special terrains and irrigated grass. Settle your core cities, build some infrastructure to handle unhappiness and multiply research and taxes, then switch to Republic.
The benefits of switching to Republic when you are ready is an extra trade arrow in each tile already producing at least one, and the option to crank luxuries up and expand cities quickly using We Love The Consul Day celebrations. There is also less corruption and greater number of cities before happiness decreases.
Another difference between Monarchy and Republic is that you can demand tribute in Monarchy, but not in Republic. You need to have more "military units" on the island/continent than the other civ in order to succeed. This can be a significant source of income in the BC years, before switching to Republic. An Early Republic is probably a better choice if you determine you are alone on a continent and there is a lot of grassy city sites with ample forests for shields.