Andrein is a béarnaise commune located on the left bank of the Gave d'Oloron 5 kilometres east of Sauveterre-de-Béarn and some 16 km south-west of Orthez. Access to the commune is by road D27 from Sauveterre-de-Bearn passing through the commune and the village and continuing east to Laàs. The D23 road from Burgaronne to L'Hôpital-d'Orion also passes through the north of the commune. The commune is mixed forest and farmland.

Located in the Drainage basin of the Adour, the southern border of the commune is formed by the Gave d'Oloron. Numerous streams flow south through the commune to the Gave d'Oloron including the Malourau and the Lourou which forms the eastern border. The northern border is formed by the Arrec Heurre which flows west to eventually join the Gave d'Oleron east of Abitain.

The commune name in Béarnese dialect and in Gascon Occitan is Andrenh. Brigitte Jobbé-Duval indicated that the name actually came from the family name Andréas with the suffix -enh. She also mentioned that the villagers were once called "cherry eaters".

The following table details the origins of the commune name and other names in the commune.

Sources:

• Raymond: Topographic Dictionary of the Department of Basses-Pyrenees, 1863, on the page numbers indicated in the table. (in French)

Origins:

• Census: Census of Béarn
• Reformation: Reformation of Béarn
• Insinuations: Insinuations of the Diocese of Oloron
• Navarrenx: Notaries of Navarrenx
• Denombrement: Denombremont of Andrein

Paul Raymond on page 6 of his 1863 dictionary noted that the commune had a Lay Abbey, a vassal of the Viscounts of Béarn.

In 1385 Andrein reported 17 fires and depended on the bailiwick of Sauveterre.

This list is incomplete; you can help by adding missing items. (April 2021)

List of Successive Mayors

The commune is part of five intercommunal structures:

• the inter-communal centre for Social Action of Sauveterre-de-Béarn;
• the Communauté de communes du Béarn des Gaves;
• the inter-communal association for the Gaves and of Saleys;
• the AEP association for the Saleys region;
• the energy association for Pyrénées-Atlantiques

The inhabitants of the commune are known as Andreinais or Andreinaises in French.

Historical population

Year Pop. ±% p.a. 1793 378 —     1800 238 −6.40% 1806 402 +9.13% 1821 271 −2.59% 1831 286 +0.54% 1836 373 +5.46% 1841 372 −0.05% 1846 364 −0.43% 1851 331 −1.88% 1856 327 −0.24% 1861 325 −0.12% 1866 332 +0.43% 1872 289 −2.29% 1876 275 −1.23% 1881 278 +0.22% 1886 242 −2.74% 1891 236 −0.50% 1896 248 +1.00%	Year Pop. ±% p.a. 1901 268 +1.56% 1906 246 −1.70% 1911 231 −1.25% 1921 218 −0.58% 1926 212 −0.56% 1931 210 −0.19% 1936 214 +0.38% 1946 184 −1.50% 1954 142 −3.19% 1962 111 −3.03% 1968 110 −0.15% 1975 99 −1.49% 1982 105 +0.84% 1990 103 −0.24% 1999 111 +0.83% 2007 129 +1.90% 2012 135 +0.91% 2017 131 −0.60%
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Source: EHESS and INSEE

Economic activity is mainly agricultural. The town is part of the Appellation d'origine contrôlée (AOC) zone of Ossau-iraty.

The Touron de Larochelle is 195 metres high.

• Emmanuel Berl, born 2 August 1892 in Vésinet (Seine-et-Oise) and died 21 September 1976 in Paris, was a journalist, historian and French essayist. In 1920 he married Jacqueline Bordes in Andrein.
• Arthur Hugenschmidt (1862–1929) stayed in Andein in 1928 and 1929 with the Countess of Viforano (daughter of Dr. Joseph Marie Alfred Beni-Barde) according to correspondence from the Presidency of the Republic.

• Communes of the Pyrénées-Atlantiques department

• Andrein on Géoportail, National Geographic Institute (IGN) website (in French)
• Andrein on the 1750 Cassini Map

Wikimedia Commons has media related to Andrein.