SharePoint Online: Delete Term Group in Term Store using PowerShell

How to Delete a Group in SharePoint Online Term Store:

• Login to your SharePoint admin center site. (E.g. https://yourdomain-admin.sharepoint.com)
  Click the "term store" link on the left navigation menu.
• From the taxonomy tree view, Select the term group which you want to delete. Click on the little arrow in the Term group Header >> Click on Delete Term Set option
  
• If the term group has any terms in it, you'll get an error message."The group has one or more term sets and can not be deleted. Move or delete all term sets from the group before deleting the Group". As the error message says, you got to delete all terms sets of the group in order to delete the group.
  
  

PowerShell to Delete a Term Group in SharePoint Online:

#Load SharePoint CSOM Assemblies
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.dll"
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.Runtime.dll"
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.Taxonomy.dll"
  
#Variables for Processing
$AdminURL = "https://crescent-admin.sharepoint.com/"
$TermGroupName ="Regions"

Try {
    #Get Credentials to connect
    $Cred = Get-Credential
    $Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($Cred.Username, $Cred.Password)

    #Setup the context
    $Ctx = New-Object Microsoft.SharePoint.Client.ClientContext($AdminURL)
    $Ctx.Credentials = $Credentials

    #Get the term store
    $TaxonomySession=[Microsoft.SharePoint.Client.Taxonomy.TaxonomySession]::GetTaxonomySession($Ctx) 
    $TermStore =$TaxonomySession.GetDefaultSiteCollectionTermStore()
    $Ctx.Load($TaxonomySession)
    $Ctx.Load($TermStore)
    $Ctx.ExecuteQuery()

    #Check if the given group exists
    $TermGroups = $TermStore.Groups
    $Ctx.Load($TermGroups)
    $Ctx.ExecuteQuery()
    $TermGroup = $TermGroups | Where-Object {$_.Name -eq $TermGroupName}
     
    If($TermGroup -ne $NULL)
    {
        #Delete all Term sets in the Term group
        $TermSets = $TermGroup.TermSets
        $Ctx.Load($TermSets)
        $Ctx.ExecuteQuery()

        $TermSets | Foreach-object {
            $_.DeleteObject()
            $Ctx.ExecuteQuery()
        }
        $TermStore.CommitAll()

        #Delete the Term Group
        $TermGroup.DeleteObject()
        $Ctx.ExecuteQuery()
     
        Write-host "Term Group '$TermGroupName' Deleted Successfully!" -ForegroundColor Green
    }
    else
    {
        Write-host "Term Group '$TermGroupName' Doesn't Exist!" -ForegroundColor Yellow
    }
}
Catch {
    write-host -f Red "Error Deleting Term Group!" $_.Exception.Message
}

PnP PowerShell to Delete a Term Group in SharePoint Online:

#Config Variables
$AdminCenterURL = "https://crescenttech-admin.sharepoint.com"

#Connect to PnP Online
Connect-PnPOnline -Url $AdminCenterURL -Credentials (Get-Credential)

#Delete the Group "Geography"
Remove-PnPTaxonomyItem "Geography" -Force

This PowerShell script removes the group "Geography" and all its children