Trade empire – The Binding Chaos Lexicon

One which includes an extranational merchant class and is wealthy in large part due to trade.

Expanded explanation

Two conditions and the first is the one doing the classifying. Wealth from trade is common and by itself makes an empire commercial rather than a trade empire in this sense. What defines the form is the merchant class being extranational, existing outside the national or state structures it moves between, which makes it answerable to none of them. A class in that position can move between societies, exploit the differences and avoid the obligations each imposes on its own people, so being outside is what makes it powerful rather than marginal. The trade empire is the second age of nations in Marsh's periodization, hierarchical trade empires including a powerful extranational merchant class, which follows the first age of autonomous and complete societies where trade happened occasionally between them rather than constituting the relation. The third age extends the same line, since a supranational empire where trade has fully abstracted the relationship between oligarchs and the people they exploit is the trade empire with the remaining distance removed and the merchants no longer merely outside but above. Nation in all of this does not mean state, being layered and overlapping societies existing across borders and generations, so a trade empire is a structure imposed on nations rather than a kind of nation. Her general verdict on the arrangement applies here as elsewhere, since the trade economy is built to facilitate power rather than financial efficiency.

In Heather Marsh’s words

Marsh classifies by the merchant class rather than by the wealth, since being outside every structure is what confers the power.

“One which includes an extranational merchant class”
Abstracting Divinity

Examples

Wealth is not the criterion: Many empires were rich from trade, and what makes this form is a merchant class answerable to none of the societies it moves between.
The second age: This is the arrangement that followed autonomous and complete societies where trade happened occasionally rather than organizing anything.
Outside becomes above: The third age keeps the structure and removes the remaining distance, so the merchants no longer merely evade states.

How others use it

Historians use trading empire for maritime and commercial powers from the Phoenicians and Venice to the Dutch and British East India Companies, and the chartered company literature documents entities exercising sovereign functions while answerable to shareholders rather than to populations. Philip Curtin's work on cross-cultural trade documented the merchant diasporas Marsh's definition centres on. World-systems theory places such arrangements in a core and periphery structure. Marsh's contribution is to make the extranational class definitional rather than characteristic, which turns a description of certain historical empires into a criterion identifying a stage.