diff --git a/lib/LaTeXML/resources/XSLT/LaTeXML-epub3.xsl b/lib/LaTeXML/resources/XSLT/LaTeXML-epub3.xsl
index 6e243e56c..b032a42e5 100644
--- a/lib/LaTeXML/resources/XSLT/LaTeXML-epub3.xsl
+++ b/lib/LaTeXML/resources/XSLT/LaTeXML-epub3.xsl
@@ -38,6 +38,14 @@
     <xsl:apply-templates select="." mode="doctype"/>
     <xsl:element name="html" namespace="{$html_ns}">
       <xsl:apply-templates select="." mode="begin"/>
+      <xsl:choose>
+        <xsl:when test="*/@xml:lang">
+          <xsl:apply-templates select="*/@xml:lang" mode="copy-attribute"/>
+        </xsl:when>
+        <xsl:otherwise><!-- the default language is English -->
+          <xsl:attribute name="lang">en</xsl:attribute>
+        </xsl:otherwise>
+      </xsl:choose>
       <xsl:apply-templates select="." mode="head"/>
       <xsl:apply-templates select="." mode="body"/>
       <xsl:apply-templates select="." mode="end"/>