diff --git a/buildkite/docker/ubuntu2004/Dockerfile b/buildkite/docker/ubuntu2004/Dockerfile
index 8306c43e34..4e40cac463 100644
--- a/buildkite/docker/ubuntu2004/Dockerfile
+++ b/buildkite/docker/ubuntu2004/Dockerfile
@@ -31,6 +31,7 @@ RUN apt-get -y update && \
     llvm \
     llvm-dev \
     lsb-release \
+    locales \
     netcat-openbsd \
     python-is-python3 \
     python2 \
@@ -66,6 +67,9 @@ WORKDIR /
 # Allow using sudo inside the container.
 RUN echo "ALL ALL=(ALL:ALL) NOPASSWD: ALL" >> /etc/sudoers
 
+# Ensure that Bazel can use its beloved ISO-8859-1 locale.
+RUN localedef -i en_US -f ISO-8859-1 en_US.ISO-8859-1
+
 FROM ubuntu2004-bazel-nojdk AS ubuntu2004-nojdk
 
 ### Install Google Cloud SDK.
diff --git a/buildkite/docker/ubuntu2204/Dockerfile b/buildkite/docker/ubuntu2204/Dockerfile
index dbdcf88cb6..fbb0661a39 100644
--- a/buildkite/docker/ubuntu2204/Dockerfile
+++ b/buildkite/docker/ubuntu2204/Dockerfile
@@ -31,6 +31,7 @@ RUN apt-get -y update && \
     llvm \
     llvm-dev \
     lsb-release \
+    locales \
     netcat-openbsd \
     openssh-client \
     python-is-python3 \
@@ -58,6 +59,9 @@ RUN apt-get -y update && \
 # Allow using sudo inside the container.
 RUN echo "ALL ALL=(ALL:ALL) NOPASSWD: ALL" >> /etc/sudoers
 
+# Ensure that Bazel can use its beloved ISO-8859-1 locale.
+RUN localedef -i en_US -f ISO-8859-1 en_US.ISO-8859-1
+
 FROM ubuntu2204-bazel-nojdk AS ubuntu2204-nojdk
 
 ### Install Google Cloud SDK.
diff --git a/buildkite/docker/ubuntu2404/Dockerfile b/buildkite/docker/ubuntu2404/Dockerfile
index 2ad9d81cbc..c67a33a819 100644
--- a/buildkite/docker/ubuntu2404/Dockerfile
+++ b/buildkite/docker/ubuntu2404/Dockerfile
@@ -30,6 +30,7 @@ RUN apt-get -y update && \
     llvm \
     llvm-dev \
     lsb-release \
+    locales \
     netcat-openbsd \
     openssh-client \
     python-is-python3 \
@@ -55,6 +56,9 @@ RUN apt-get -y update && \
 # Allow using sudo inside the container.
 RUN echo "ALL ALL=(ALL:ALL) NOPASSWD: ALL" >> /etc/sudoers
 
+# Ensure that Bazel can use its beloved ISO-8859-1 locale.
+RUN localedef -i en_US -f ISO-8859-1 en_US.ISO-8859-1
+
 FROM ubuntu2404-bazel-nojdk AS ubuntu2404-nojdk
 
 ### Install Google Cloud SDK.