diff --git a/.gitmodules b/.gitmodules
index f6efec68b..30c1bf668 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -7,3 +7,6 @@
 [submodule "ext/sundials"]
 	path = ext/sundials
 	url = https://github.com/Cantera/sundials-mirror
+[submodule "ext/eigen"]
+	path = ext/eigen
+	url = https://github.com/Cantera/eigen-mirror.git
diff --git a/ext/eigen b/ext/eigen
new file mode 160000
index 000000000..c6ef117db
--- /dev/null
+++ b/ext/eigen
@@ -0,0 +1 @@
+Subproject commit c6ef117db0a5d72ad0b0239ab1f6dfc3291c398e