Index: binaries/data/mods/public/maps/random/guadalquivir_river.js
===================================================================
--- binaries/data/mods/public/maps/random/guadalquivir_river.js
+++ binaries/data/mods/public/maps/random/guadalquivir_river.js
@@ -78,13 +78,19 @@
 		new TileClassPainter(clLand)
 	]);
 
-var playerPosition = playerPlacementCustomAngle(
-	fractionToTiles(0.35),
-	continentCenter,
-	i => Math.PI * (-0.46 / numPlayers * (i + i % 2) - (i % 2) / 2))[0].map(pos => pos.rotateAround(startAngle, mapCenter));
+var playerIDs = sortAllPlayers();
+var playerPosition = playerPlacementArcs(
+	playerIDs,
+	continentCenterR,
+ 	fractionToTiles(0.35),
+	-startAngle + Math.PI * 0.15,
+	-startAngle - Math.PI * 0.5,
+	-startAngle - Math.PI * 0.5,
+	-startAngle - Math.PI * 1.15);
+
 
 placePlayerBases({
-	"PlayerPlacement": [primeSortAllPlayers(), playerPosition],
+	"PlayerPlacement": [playerIDs, playerPosition],
 	"PlayerTileClass": clPlayer,
 	"BaseResourceClass": clBaseResource,
 	"Walls": false,
Index: binaries/data/mods/public/maps/random/jebel_barkal.js
===================================================================
--- binaries/data/mods/public/maps/random/jebel_barkal.js
+++ binaries/data/mods/public/maps/random/jebel_barkal.js
@@ -392,11 +392,16 @@
 Engine.SetProgress(30);
 
 g_Map.log("Computing player locations");
-const playerIDs = primeSortAllPlayers();
-const playerPosition = playerPlacementCustomAngle(
-	fractionToTiles(0.38),
-	mapCenter,
-	i => Math.PI * (-0.42 / numPlayers * (i + i % 2) - (i % 2) / 2))[0];
+const playerIDs = sortAllPlayers();
+const playerCenter = new Vector2D(0, fractionToTiles(0.05)).rotate(-riverAngle).add(mapCenter).round();
+const playerPosition = playerPlacementArcs(
+	playerIDs,
+	playerCenter,
+	fractionToTiles(0.4),
+	riverAngle + Math.PI * 0.1,
+	riverAngle - Math.PI * 0.45,
+	riverAngle - Math.PI * 0.55,
+	riverAngle - Math.PI * 1.1);
 
 if (!isNomad())
 {
Index: binaries/data/mods/public/maps/random/pyrenean_sierra.js
===================================================================
--- binaries/data/mods/public/maps/random/pyrenean_sierra.js
+++ binaries/data/mods/public/maps/random/pyrenean_sierra.js
@@ -159,11 +159,18 @@
 	}
 }
 
+var playerIDs = sortAllPlayers();
+var playerPosition = playerPlacementArcs(
+	playerIDs,
+	mapCenter,
+	fractionToTiles(0.35),
+	oceanAngle + Math.PI * 0.1,
+	oceanAngle + Math.PI * 0.9,
+	oceanAngle - Math.PI * 0.1,
+	oceanAngle - Math.PI * 0.9);
+
 placePlayerBases({
-	"PlayerPlacement": [primeSortAllPlayers(), ...playerPlacementCustomAngle(
-		fractionToTiles(0.35),
-		mapCenter,
-		i => oceanAngle + Math.PI * (i % 2 ? 1 : -1) * ((1/2 + 1/3 * (2/numPlayers * (i + 1 - i % 2) - 1))))],
+	"PlayerPlacement": [playerIDs, playerPosition],
 	"PlayerTileClass": clPlayer,
 	"BaseResourceClass": clBaseResource,
 	"CityPatch": {
Index: binaries/data/mods/public/maps/random/rmgen-common/player.js
===================================================================
--- binaries/data/mods/public/maps/random/rmgen-common/player.js
+++ binaries/data/mods/public/maps/random/rmgen-common/player.js
@@ -534,6 +534,31 @@
 	return primeSortPlayers(sortAllPlayers());
 }
 
+/*
+ * Separates playerIDs into two arrays such that teammates are in the same array.
+ * This assumes that playerIDs already has teammates grouped together.
+ */
+function partitionPlayers(playerIDs)
+{
+	let teams = playerIDs.reduce((list, i) => {
+		let length = list.length;
+		let team = getPlayerTeam(i);
+		if (!length || team == -1 || team != getPlayerTeam(list[length - 1][0]))
+			list.push([i]);
+		else
+			list[length - 1].push(i);
+		return list;
+	}, []);
+
+	// Use the greedy algorithm
+	teams.sort((a, b) => b.length - a.length);
+	return teams.reduce(([a, b], c) => {
+		if (a.length > b.length)
+			return [a, b.concat(c)];
+		return [a.concat(c), b];
+	}, [[], []]);
+}
+
 /**
  * Determine player starting positions on a circular pattern.
  */
@@ -565,6 +590,34 @@
 }
 
 /**
+ * Returns player starting positions located on two arcs, with teammates placed on the same arc.
+ */
+function playerPlacementArcs(playerIDs, center, radius, startAngle1, endAngle1, startAngle2, endAngle2)
+{
+	let [east, west] = partitionPlayers(playerIDs);
+	let eastPosition = distributePointsOnCircularSegment(
+		east.length + 1,
+		endAngle1 - startAngle1,
+		startAngle1,
+		radius,
+		center
+	)[0].slice(1);
+	let westPosition = distributePointsOnCircularSegment(
+		west.length + 1,
+		endAngle2 - startAngle2,
+		startAngle2,
+		radius,
+		center
+	)[0].slice(1);
+	return playerIDs.map(id => {
+		let i = east.indexOf(id);
+		if (i != -1)
+			return eastPosition[i].round();
+		return westPosition[west.indexOf(id)].round();
+	});
+}
+
+/**
  * Returns player starting positions located on two parallel lines, typically used by central river maps.
  * If there are two teams with an equal number of players, each team will occupy exactly one line.
  * Angle 0 means the players are placed in north to south direction, i.e. along the Z axis.