Business Partner Country & Language are mandatory in SAP S/4HANA On Premise
This blog explains “Country” and “Language” fields of Business Partner are mandatory.
This is valid for any version of SAP S/4HANA.
Explain reasons why:
Both two fields are needed to subsequent functions. So, SAP standard program is coded permanently to keep the two fields mandatory, although the customizing of the filed attributes are set as option.