Exhibit 21.1

LIST OF SUBSIDIARIES OF ONEBEACON INSURANCE GROUP, LTD.
as of December 31, 2007

|Subsidiary                                   |  | Jurisdiction of Incorporation
|-------------------------------------------- |  | -----------------------------
|A. W. G. Dewar, Inc.                         |  | Massachusetts                
|Adirondack AIF, LLC                          |  | New York                     
|Adirondack Insurance Exchange                |  | New York                     
|Atlantic Specialty Insurance Company         |  | New York                     
|AutoOne Insurance Agency, Inc.               |  | Delaware                     
|AutoOne Insurance Company                    |  | New York                     
|AutoOne Management Company, Inc.             |  | Delaware                     
|AutoOne Select Insurance Company             |  | New York                     
|The Camden Fire Insurance Association        |  | New Jersey                   
|The Employers' Fire Insurance Company        |  | Massachusetts                
|Essentia Insurance Company                   |  | Missouri                     
|Farmers and Merchants Insurance Company      |  | Oklahoma                     
|Fund American Companies, Inc.                |  | Delaware                     
|Fund American Enterprises Holdings, Inc.     |  | Delaware                     
|Fund American Financial Services, Inc.       |  | Delaware                     
|Homeland Insurance Company of New York       |  | New York                     
|Houston General Insurance Company            |  | Texas                        
|Houston General Insurance Exchange           |  | Texas                        
|Houston General Insurance Management Company |  | Texas                        
|Massachusetts Homeland Insurance Company     |  | Massachusetts                
|Mill Shares Holdings (Bermuda) Ltd.          |  | Bermuda                      
|National Marine Underwriters, Inc.           |  | Delaware                     
|New Jersey Skylands Management LLC           |  | Maryland                     
|The Northern Assurance Company of America    |  | Massachusetts                
|OneBeacon America Insurance Company          |  | Massachusetts                
|OneBeacon Holdings (Gibraltar) Limited       |  | Gibraltar                    
|OneBeacon Holdings (Luxembourg) S.à.r.l.     |  | Luxembourg                   
|OneBeacon Insurance Company                  |  | Pennsylvania                 
|OneBeacon Insurance Group LLC                |  | Delaware                     
|OneBeacon Lloyd's, Inc.                      |  | Texas                        
|OneBeacon Lloyd's of Texas                   |  | Texas                        
|OneBeacon Midwest Insurance Company          |  | Wisconsin                    
|OneBeacon Professional Partners, Inc.        |  | Delaware                     
|OneBeacon Risk Management, Inc.              |  | Delaware                     
|Pennsylvania General Insurance Company       |  | Pennsylvania                 
|Potomac Insurance Company                    |  | Pennsylvania                 
|TCH Insurance Agency, Inc.                   |  | Massachusetts                
|Traders & General Insurance Company          |  | Texas                        
|WM Belvaux (Luxembourg) S.à.r.l.             |  | Luxembourg                   
|WM Findel (Luxembourg) S.à.r.l.              |  | Luxembourg                   
|WM Kehlen (Luxembourg) S.à.r.l.              |  | Luxembourg                   
|WM Queensway (Gibraltar) Limited             |  | Gibraltar                    
|York Insurance Company of Maine              |  | Maine                        

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