LaTeX Forum

\documentclass[12pt,a4paper,oneside,english]{scrartcl}  

\usepackage[authordate15,backend=biber]{biblatex-chicago}
\addbibresource{MetaphorsEcon.bib}

\usepackage{babel}
\usepackage{microtype}
\usepackage[left=2cm, right=2cm,top=2cm, bottom=2cm] {geometry}
\usepackage[onehalfspacing]{setspace}
\usepackage{graphicx}
\usepackage{eurosym}
\usepackage{amsmath}
\usepackage{mathtools}
\usepackage{amssymb}
\usepackage[all, error]{onlyamsmath}
\usepackage{amsfonts}
\usepackage{float}
\usepackage{epsfig}
\usepackage{epstopdf}
\usepackage{wrapfig}
\usepackage{kpfonts}
\usepackage{bookmark}
\usepackage{caption}
\usepackage{wrapfig} 
\usepackage{indentfirst}
\usepackage{chemmacros}
\usepackage[super]{nth}


\begin{document}


\par
\begingroup
\leftskip=1cm
\noindent 

Hier soll der eingerückte Text in Schriftgröße 10pt stehen
\par
\endgroup


\end{document}

\documentclass[12pt,a4paper,oneside,english]{scrartcl}  
\usepackage{babel}
\usepackage{mwe}
\begin{document}
\blindtext
\begin{addmargin}[1cm]{0cm}\footnotesize
With language option \texttt{english} and without \texttt{ngerman} we should
write the document in English---not in German!
\end{addmargin}
\blindtext
\begin{labeling}{\hspace{\dimexpr 1cm-\labelsep}}\footnotesize
\item Or with some vertical distance before and after this indented text.
\end{labeling}
\blindtext
\end{document}