As you see, the sales persons in above table are unique. Therefore, we can list only unique countries and then count sales persons based on these unique countries with the COUNTIF function. Please do as follows:

1. Copy the Country column (which you will count by), and paste it to a blank column. In our case, we pasted the Country column in Column E.

2. Keep selecting the new pasted column, and click Data > Remove Duplicates.

3. In the opening Remove Duplicates dialog box, click the OK button.

Another dialog box comes out and shows how many duplicates have been removed. Just close this dialog box.

Till now we have listed the unique countries in the Column E.

4. Select a blank cell besides the unique country list, says Cell F2, enter the formula =COUNTIF($A$1:$A$24,E2) into it, and then drag this cell’s Fill Handle to apply this formula to the range as you need.

Note: In above formula, $A$1:$A$24 is the country column in original sales person table, and E2 is the country in the unique country list that you will count by.
So far we have counted these sales persons by country as below screenshot shown:

The second method will introduce Kutools for Excel’s Advanced Combine Rows utility to simplify your counting work, and batch count cells/records by groups with several clicks in Excel. Please do as follows:

1. Select the sales person table, and click Kutools > Merge & Split > Advanced Combine Rows. See screenshot:

2. In the opening Combine Rows Based on Column dialog box, please do as below screenshot shown:

3. Click the Ok button. Then you will see the sales persons have been counted by country as below screenshot shown:

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