multilingual — script and language setup

Decision: babel or polyglossia?

Rule of thumb: babel for pdflatex+Latin; polyglossia for xelatex/lualatex with anything beyond Latin. polyglossia is XeLaTeX/LuaLaTeX-only.

Source: polyglossia manual at https://texdoc.org/serve/polyglossia.pdf/0.

babel (pdflatex / Latin scripts)

\usepackage[main=english, french, german, spanish]{babel}
% In body:
\selectlanguage{french}              % switch zone
Bonjour le monde.
\foreignlanguage{german}{Hallo Welt} % inline

main= sets the document language. Hyphenation patterns load automatically per language. Babel adapts captions ("Figure"→"Figura"), date formats, quote styles.

Source: https://ctan.org/pkg/babel.

polyglossia (xelatex / lualatex / non-Latin or modern fonts)

\usepackage{fontspec}
\usepackage{polyglossia}
\setdefaultlanguage{english}
\setotherlanguages{french, arabic, hindi}
% Per-script font:
\newfontfamily\arabicfont[Script=Arabic]{Amiri}
\newfontfamily\hindifont[Script=Devanagari]{Noto Serif Devanagari}
% In body — same commands as babel:
\selectlanguage{french}
\foreignlanguage{arabic}{مرحبا بالعالم}

Pitfalls (polyglossia):

• Does NOT accept package-option language declarations. \usepackage[french]{polyglossia} is wrong; use \setotherlanguages{...}.
• Other languages must be explicitly declared (no lazy reference).
• Variants come via options: \setdefaultlanguage[variant=british]{english}.

Source: https://ctan.org/pkg/polyglossia · polyglossia PDF (linked above).

RTL setup (Arabic, Hebrew, Persian)

Recommended stack: LuaLaTeX + polyglossia + fontspec + luabidi (auto).

\documentclass{article}
\usepackage{fontspec}
\usepackage{polyglossia}
\setdefaultlanguage{english}
\setotherlanguage{arabic}
\newfontfamily\arabicfont[Script=Arabic]{Amiri}    % free, traditional Naskh
\begin{document}
English paragraph here.
\begin{arabic}
هذا نص عربي.
\end{arabic}
\end{document}

Compile: lualatex main.tex or latexmk -pdflua main.tex.

Recommended Arabic fonts (free, Unicode, well-shaped): Amiri (Khaled Hosny), Scheherazade New (SIL), Noto Naskh Arabic, Reem Kufi (display only). Hebrew: SBL Hebrew, Ezra SIL, David CLM, Frank Ruhl Hofshi, Noto Serif Hebrew. Persian: same as Arabic plus XB Niloofar, Vazirmatn.

Mixed direction: inside an RTL paragraph, wrap LTR fragments with \foreignlanguage{english}{...} or \LR{...} (and \RL{...} for the inverse). Without this, Latin numbers, punctuation, and English words drift visually.

XeLaTeX path: same packages but uses bidi (auto-loaded). LuaLaTeX is generally smoother for bidi due to TeX engine's native bi-directional layout.

Sources: https://ctan.org/pkg/bidi, https://ctan.org/pkg/luabidi, polyglossia RTL chapter.

CJK setup

Chinese (XeLaTeX):

\documentclass[UTF8]{ctexart}              % loads xeCJK + Chinese class defaults
\begin{document}
你好，世界。Mixed Chinese/English works automatically.
\end{document}

ctex is the canonical Chinese-typesetting bundle; it ships ctexart, ctexrep, ctexbook classes. By default uses XeLaTeX; can be pointed at LuaLaTeX with \documentclass[lua]{ctexart} (newer ctex).

Japanese (LuaLaTeX):

\documentclass{article}
\usepackage{luatexja-fontspec}
\setmainjfont{Noto Serif CJK JP}
\setsansjfont{Noto Sans CJK JP}
\begin{document}
こんにちは、世界。Mixed Japanese/English.
\end{document}

Compile: lualatex (luatexja is LuaLaTeX-only).

Korean (LuaLaTeX similar): replace fonts with Noto Serif CJK KR etc.

Generic CJK on XeLaTeX without ctex/luatexja:

\usepackage{xeCJK}
\setCJKmainfont{Noto Serif CJK SC}
\setCJKsansfont{Noto Sans CJK SC}
\setCJKmonofont{Noto Sans Mono CJK SC}

Recommended fonts:

• Simplified Chinese: Noto Serif CJK SC, Source Han Serif SC.
• Traditional Chinese: Noto Serif CJK TC, Source Han Serif TC.
• Japanese: Noto Serif CJK JP, Source Han Serif JP, IPAex Mincho.
• Korean: Noto Serif CJK KR, Source Han Serif KR, Nanum Myeongjo.

Pitfalls:

• Default font for xeCJK is "Fandol" (Chinese) — inappropriate for JP/KR. Always set explicitly per language.
• CJK leading typically wants \linespread{1.3} or so — defaults are too tight.
• Loading order: xeCJK after fontspec after polyglossia (if used).

Sources: https://ctan.org/pkg/xecjk, https://ctan.org/pkg/ctex, https://ctan.org/pkg/luatexja.

Indic / Devanagari / Tamil / Thai

Recommended stack: LuaLaTeX + polyglossia + fontspec + Noto fonts.

\documentclass{article}
\usepackage{fontspec}
\usepackage{polyglossia}
\setdefaultlanguage{english}
\setotherlanguage{hindi}
\newfontfamily\hindifont[Script=Devanagari]{Noto Serif Devanagari}
\begin{document}
Hello in Hindi: \texthindi{नमस्ते दुनिया}.
\end{document}

Script=Devanagari (or Script=Tamil, Script=Bengali, etc.) is required so the OpenType shaper builds conjuncts and half-forms. Without it, glyph shapes are right but ligature placement breaks.

Recommended fonts: Noto Serif/Sans for {Devanagari, Tamil, Thai, Bengali, Malayalam, Kannada, Telugu}; Sahadeva and Annapurna SIL for Sanskrit.

polyglossia language names: hindi, marathi, sanskrit, tamil, thai, malayalam, kannada, telugu, bengali.

Pitfalls:

• Forgetting Script=Devanagari (or equivalent) on \newfontfamily.
• pdflatex won't work for Unicode Indic — use lualatex.
• Hyphenation and line-breaking for Indic scripts are limited; rely on script-specific rules from polyglossia + LuaTeX.

Sources: polyglossia manual sections on Indic scripts.

Direction-aware hyphenation

When the document has multiple scripts, ensure hyphenation patterns are loaded for each:

• babel: handled per language option.
• polyglossia: handled per \setotherlanguage{...} call.

If a language is set but hyphenation is wrong, check texlive-lang-<lang> is installed (TeX Live splits language patterns into per-language packages).

When uncertain

Language-specific options (variants, hyphenation overrides, font features for a specific script) — invoke /academic-latex:docs-lookup with the question. polyglossia options especially are version-sensitive; do not guess.

Last verified

2026-05-09 — polyglossia, babel, xeCJK, ctex, luatexja, bidi/luabidi at CTAN; font recommendations from Google Noto and SIL catalog.