diff --git a/requirements.txt b/requirements.txt
index 5316addb..6229f143 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -66,7 +66,7 @@ pyyaml==6.0.3
     # via pybtex
 requests==2.34.2
     # via sphinx
-roman-numerals-py==3.1.0
+roman-numerals-py==4.1.0
     # via sphinx
 setuptools-scm==9.2.2
     # via libsemigroups_pybind11 (pyproject.toml::build-system.requires)