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Flags of São Tomé & Príncipe

Uninhabited until Portuguese sailors found the twin volcanic islands in the 1470s, São Tomé became one of the earliest large-scale sugar-plantation colonies built on enslaved African labor anywhere in the Atlantic world, and later a cocoa economy still run largely on forced and indentured contract labor well into the 20th century — three flags across five hundred years, from the Portuguese crown to a one-party Marxist republic to the multiparty state of today.

Because the archipelago had no prior inhabitants, this page's flag lineage begins directly with Portugal's own arrival rather than with any precolonial entry — there is no earlier political history to document.

Scope of this page: the islands of São Tomé and Príncipe, from their 1470s discovery to present, three political-flag eras. Portugal's own national flag changed twice during the nearly five centuries of colonial rule (the 1830 blue-and-white constitutional-monarchy flag, then the green-and-red republican flag adopted in 1911 after the 1910 revolution); those two Portuguese eras are combined into one colonial entry below rather than split, since the change reflects Portugal's own domestic politics rather than any shift in the islands' status.

One archipelago, two islands, three flags

São Tomé & Príncipe's own real coastline, traced whole — there is no internal split to draw. The two islands sit roughly 150 km apart; Príncipe (north) has had its own semi-autonomous regional government since 1995, but both islands have shared a single national flag throughout. Press play, or drag the slider.

Two islands, one flag, always. Unlike several other pages in this atlas, there is no documented moment when São Tomé and Príncipe flew different flags from each other — both were part of the same Portuguese colonial administration, then the same independent republic, from the very start of their political history.

Real traced coastline for both islands; the Gabon distance label is a schematic direction indicator, not to scale.

green-yellow-green with red triangle and two black stars — unchanged since 1975

1975 – present

Democratic Republic of São Tomé & Príncipe

Republic, independentManuel Pinto da CostaSecular (no state religion)

Migration & conquest:Emigration: to Portugal, Angola & Gabon (1975–)

Who & why: independence arrives on 12 July 1975 following the Carnation Revolution's collapse of Portugal's colonial empire, with Manuel Pinto da Costa's MLSTP taking power as the sole legal party in a Marxist-aligned one-party state. The country transitions peacefully to multiparty democracy in 1990–91, becoming one of the more politically stable states to emerge from Portuguese Africa, with the same flag flying throughout both eras.

What it represents: green for the islands' vegetation, yellow for the cocoa harvest central to the economy, the red triangle for the struggle for independence, and two black stars for São Tomé and Príncipe themselves — colors shared with several other former Portuguese African colonies' independence movements.

Paint guide

Proportions1:2.

LayoutGreen-yellow-green horizontal bands (yellow twice the width of each green), a red hoist triangle, and two black five-pointed stars centered on the yellow band.

Green#12AD2B

Yellow#FCD116

Red#D21034

the Portuguese Republic's green-and-red flag over the colony

1471 – 1975

Portuguese colonial rule

Colonial territoryJoão de SantarémRoman Catholic (colonial establishment)

Migration & conquest:Immigration: Portuguese settlers & enslaved Africans (from 1471)Immigration: contract laborers from Angola, Cape Verde & Mozambique (late 1800s–1953)

Ruling house:House of AvisHouse of HabsburgHouse of Braganza

Who & why: Portuguese navigators reach the uninhabited islands around 1470–71 and begin settlement soon after, importing enslaved Africans to build one of the first major sugar-plantation economies in the Atlantic world by the 1500s. Sugar declines by the 17th century as production shifts to Brazil, and São Tomé becomes chiefly a staging point in the slave trade before cocoa, introduced in the 19th century, remakes the economy — cultivated on large plantations (roças) that continue relying on forced and contract labor from other Portuguese colonies until a 1953 massacre of protesting workers draws international attention. Nationalist agitation grows through the 1960s–70s, and Portugal's own 1974 Carnation Revolution opens the door to independence the following year.

What it represents: Portugal's own national flag, flown over the colony throughout; the civil ensign changed from a blue-and-white design to the current green-and-red one after Portugal's 1910 republican revolution, a domestic Portuguese change rather than a colonial one.

Paint guide

Proportions2:3.

LayoutGreen hoist third, red fly two-thirds, with the Portuguese armillary sphere and shield centered on the boundary (from 1911; a blue-and-white flag with royal arms flew before then).

Green#046A38

Red#FF0000

Armillary sphere, gold#FCD116

Reading the tags

Colonial territory — governed as part of a foreign empire

Republic, independent — sovereign under its own government

Leader — the named ruler most associated with the era's start

State religion — the official/established faith, not the population's

Find the records

Family history research for São Tomé & Príncipe lives in a different project, Record Atlas, which maps which archive actually holds the paper for a given place and era.

Search Record Atlas for São Tomé & Príncipe →

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