Simulate the historically lucrative Indian Ocean trade

[Shoebopp]

First, make a backup of export_descr_buildings.txt

Open export_descr_buildings.txt and Ctrl+F for these lines

levels port shipwright dockyard naval_drydock

You should see something like

building port
{
	levels port shipwright dockyard naval_drydock
	{
		port city requires factions { all, } and not building_present govslave and building_present govrome or building_present govcarthage or building_present govkh or building_present govhayasdan or building_present govparthia or building_present govaedui or building_present govarverni or building_present govcasse or building_present govluso or building_present govsweboz or building_present govgetai or building_present govsaba or building_present govsauro or building_present_min_level govnumidia numidia3 or building_present govgandhara or building_present govlugia or building_present govbospor or building_present govarevaci or building_present govboii or building_present govnabatu or building_present_min_level govsaka saka_admin or building_present_min_level govbaktria baktria2 or building_present_min_level govmakedonia makedonia2 or building_present_min_level govpergamon pergamon2 or building_present_min_level govptolemaioi ptolemaioi2 or building_present_min_level govepeiros epeiros2 or building_present_min_level govpontos pontos2 or building_present_min_level govseleukid seleukid1 or building_present govallied
		{
			capability
			{
				recruit_pool "generic ship germanic"  1  0.05  1  0  requires factions { cul_1, cul_2, cul_3, cul_4, cul_5, f_sauromatae, f_saka, cul_7, } and hidden_resource baltic
				recruit_pool "generic ship germanic"  1  0.05  1  0  requires factions { cul_1, cul_2, cul_3, cul_4, cul_5, f_sauromatae, f_saka, cul_7, } and not hidden_resource celtic and hidden_resource germania
				recruit_pool "generic ship pontomora"  1  0.05  1  0  requires factions { cul_1, cul_2, cul_3, cul_4, cul_5, f_sauromatae, f_saka, cul_7, } and not hidden_resource liburnes and hidden_resource celtic or hidden_resource briton or hidden_resource lusitan
				recruit_pool "generic ship pontomora"  1  0.05  1  0  requires factions { cul_1, cul_2, cul_3, cul_4, cul_5, f_sauromatae, f_saka, cul_7, } and hidden_resource celtic and hidden_resource liburnes and not region_religion rel_g 30 and not region_religion rel_h 30
				recruit_pool "generic ship pontomora"  1  0.05  1  0  requires factions { cul_5, } and hidden_resource iberia or hidden_resource dacia
				recruit_pool "generic ship pontomora"  1  0.05  1  0  requires factions { cul_1, cul_2, cul_3, cul_4, f_sauromatae, f_saka, cul_7, } and hidden_resource dacia and not region_religion rel_h 30 and not region_religion rel_g 30
				recruit_pool "generic ship pontomora"  1  0.05  1  0  requires factions { cul_5, f_sauromatae, f_saka, } and hidden_resource sarmatian

That's the code for the capabilities that ports offer you. Here is the code to copy and paste into the capabilities brackets

				;;; Indian Ocean trade
				income_bonus bonus 500 requires factions { all, } and not hidden_resource hellen1 and hidden_resource egypt or hidden_resource ethiopia
				income_bonus bonus 500 requires factions { all, } and not hidden_resource hellen1 and not hidden_resource daha and not hidden_resource horde_target and hidden_resource eastern 
				income_bonus bonus 500 requires factions { all, } and hidden_resource arabian and not hidden_resource eastern
				income_bonus bonus 500 requires factions { all, } and hidden_resource indo

You should result in something like this

building port
{
	levels port shipwright dockyard naval_drydock
	{
		port city requires factions { all, } and not building_present govslave and building_present govrome or building_present govcarthage or building_present govkh or building_present govhayasdan or building_present govparthia or building_present govaedui or building_present govarverni or building_present govcasse or building_present govluso or building_present govsweboz or building_present govgetai or building_present govsaba or building_present govsauro or building_present_min_level govnumidia numidia3 or building_present govgandhara or building_present govlugia or building_present govbospor or building_present govarevaci or building_present govboii or building_present govnabatu or building_present_min_level govsaka saka_admin or building_present_min_level govbaktria baktria2 or building_present_min_level govmakedonia makedonia2 or building_present_min_level govpergamon pergamon2 or building_present_min_level govptolemaioi ptolemaioi2 or building_present_min_level govepeiros epeiros2 or building_present_min_level govpontos pontos2 or building_present_min_level govseleukid seleukid1 or building_present govallied
		{
			capability
			{
				;;; Indian Ocean trade
				income_bonus bonus 500 requires factions { all, } and not hidden_resource hellen1 and hidden_resource egypt or hidden_resource ethiopia
				income_bonus bonus 500 requires factions { all, } and not hidden_resource hellen1 and not hidden_resource daha and not hidden_resource horde_target and hidden_resource eastern 
				income_bonus bonus 500 requires factions { all, } and hidden_resource arabian and not hidden_resource eastern
				income_bonus bonus 500 requires factions { all, } and hidden_resource indo

What this does is offer a lucrative 500 income bonus to all Red Sea, Persian Gulf, and Indian Ocean provinces. The above code snippet is just for level 1 ports btw. You should copy and paste the Indian Ocean trade lines into the shipwright, dockyard, and naval_drydock capabilities as well. Here's the one for shipwright

shipwright city requires factions { all, } and not building_present hinterland_pastoral_city and not building_present govslave and building_present_min_level govsaka saka_autsat or building_present govrome or building_present govcarthage or building_present govkh or building_present govhayasdan or building_present govparthia or building_present govaedui or building_present govarverni or building_present govcasse or building_present govluso or building_present govsweboz or building_present govgetai or building_present govsaba or building_present govsauro or building_present_min_level govnumidia numidia4 or building_present govgandhara or building_present govlugia or building_present govbospor or building_present govarevaci or building_present govboii or building_present govnabatu or building_present_min_level govbaktria baktria2 or building_present_min_level govmakedonia makedonia2 or building_present_min_level govpergamon pergamon2 or building_present_min_level govptolemaioi ptolemaioi2 or building_present_min_level govepeiros epeiros2 or building_present_min_level govpontos pontos3 or building_present_min_level govseleukid seleukid1 or building_present_min_level govallied oligone
		{
			capability
			{
				;;; Indian Ocean trade
				income_bonus bonus 1000 requires factions { all, } and not hidden_resource hellen1 and hidden_resource egypt or hidden_resource ethiopia
				income_bonus bonus 1000 requires factions { all, } and not hidden_resource hellen1 and not hidden_resource daha and not hidden_resource horde_target and hidden_resource eastern 
				income_bonus bonus 1000 requires factions { all, } and hidden_resource arabian and not hidden_resource eastern
				income_bonus bonus 1000 requires factions { all, } and hidden_resource indo

Notice that the bonus was upgraded to 1000. You can pick and choose which values to use for the income bonus for each level of ports, and be generous! The trade from India to Egypt and other Middle Eastern destinations was historically LUCRATIVE as hell. The Ptolemies historically also failed to tax the trade properly, but the Romans sure did. Watch this video for additional history on how the Indian Ocean trade basically bankrolled the Roman Empire https://www.youtube.com/watch?v=BaCaFpAtm48 .

The result of this simple savegame compatible change? The Sabaeans will swim in money, while the Ptolemies now have a real financial incentive to conquer and tidy up their southern lands. The Seleucids and Taksashilans meanwhile enjoy a little extra cash from their Persian Gulf provinces.

[Shoebopp]

Hotfix: Sousa isn't covered by the income bonus. Here's an extra line to add to the Indian Ocean trade code

				income_bonus bonus 500 requires factions { all, } and hidden_resource hellen2 and hidden_resource horde_target

[Roma_Victrix]

Interesting! Not a bad idea. Also yes, historically it was insanely lucrative for all parties involved with the selling of Chinese silk and Indian spice.

I like that you bumped the bonus up to 1,000 mnai, but if we're being realistic, under the Roman Empire, those settlements would have the equivalent of like 10,000+ given the enormous amount of riches that you rightly stated were responsible for bankrolling the empire itself. Would be unfair to other factions, though.

[Mamlaz]

Superb immersive idea

however I disagree with giving all the coastal provinces such a bonus, but rather would suggest a more powerful bonus for key tradehub regions as they were, namely;

Spoiler Alert, click show to read: 

The most important aspect of said Indian route was the colossal demand for such goods in the Mediterranean.

This would reflect this, also make Egypt even more important to hold, as the three provinces(Two in Egypt and one Nabatean) next to each other would represent the sea-to-sea transit.

[Shoebopp]

That's sounds reasonable. I'd add Axum to the list of trade hubs, since that Kings and Generals video did mention that Axum was a hopping stone on the way to Hellenistic markets.

[Mamlaz]

Not in EB's timeline though, Axum's trade hubs flourished from the 2nd century AD onwards, before that it was the tip of Arabia that served as the waypoint.

Also the isles near it, which is why the Roman navy took it for themselves at one point;

https://www.youtube.com/watch?v=NeUC...nel=StefanMilo

[Shoebopp]

Another hotfix: the EDB line for Sousa accidentally also adds income to Memphis. Here's the fixed line

	income_bonus bonus 1000 requires factions { all, } and hidden_resource eastern and hidden_resource hellen2 and hidden_resource horde_target

The old incorrect line was

	income_bonus bonus 1000 requires factions { all, } and hidden_resource hellen2 and hidden_resource horde_target

[Shoebopp]

Another hotfix: consider adding these bonuses to the following buildings (Ctrl+F these lines to find the buildings to which you'll add the income bonus)

building port_garrison

building hinterland_roads

building roads_garrison

MAKE SURE TO INSERT THE FOLLOWING REQUIREMENTS TO THE BONUSES

and building_present port

so that a bonus line would look like

income_bonus bonus 1500 requires factions { all, } and building_present port and not hidden_resource hellen1 and hidden_resource egypt or hidden_resource ethiopia

The reason is that the requirements for the ports are too lax and assume that only coastal settlements can build ports and thus get the bonus. If you don't add

and building_present port

then vast swathes of Persian, Indian, and African provinces, even those not bordering Indian Ocean trade routes, will get bonuses.

For the roads_garrison, keep the income bonus for roads_garrison_two, roads_garrison_three, roads_garrison_four the same. The reason is that roads_garrison_two represents the highest levels of road security infrastructure, roads_garrison_three just adds Jewish recruitment, and roads_garrison_three just adds veteran Roman legionary recruitment. This does mean that, should you add 500 income for each upgrade for ports, ports garrisons, roads, and roads garrisons, a maxed out qualifying settlement would generate 6000 in extra income alone. It's up to you to decide if this massive income represents a fully exploited Indian Ocean trade accurately.

[Cloacky]

How do you add these bonuses? Just insert them randomly, somewhere below these buildings? Sorry, I'm new to modding.